View source for Japan Socialist Party

{{Short description|Political party active in Japan from 1945 to 1996}}
{{About|the Japanese political party that existed from 1945 to 1996}}
{{Use dmy dates|date=August 2021}}
{{Infobox political party
| name             = Japan Socialist Party
| native_name      = {{nobold|{{Nihongo2|日本社会党}}<br />{{transliteration|ja|Nippon shakai-tō}} or {{transliteration|ja|Nihon shakai-tō}}}}
| logo             = 日本社会党ロゴ.svg
| colorcode        = {{party color|Japan Socialist Party}}
| foundation       = {{start date and age|1945|11|02|df=y}}
| dissolved        = {{end date and age|1996|01|19|df=y}}
| successor        = [[Social Democratic Party (Japan)|Social Democratic Party]]
| headquarters     = Social & Cultural Center 1-8-1 [[Nagatachō, Tokyo|Nagata-cho]], [[Chiyoda, Tokyo|Chiyoda-ku]], [[Tokyo]]
| newspaper        = ''{{ill|Shakai Shimpō|ja|社会新報}}''<ref>{{cite web |url=https://kotobank.jp/word/%E7%A4%BE%E4%BC%9A%E6%96%B0%E5%A0%B1-75618 |script-title=ja:社会新報とは § ブリタニカ国際大百科事典 小項目事典の解説 |trans-title=What is Shakai Shimpō? § The ''Encyclopædia Britannica: Micropædia''{{'}}s explanation |access-date=22 November 2020 |website=kotobank.jp |publisher=[[The Asahi Shimbun Company]] |language=ja}}</ref>
| leader           = {{ublist
 | [[Tetsu Katayama]] (first)
 | [[Tomiichi Murayama]] (last)
}}
| ideology         = {{ubl|class = nowrap
 | [[Socialism]]
 | [[Progressivism]]
 | [[Pacificism]]
 | '''Factions:'''
 | [[Democratic socialism]]{{cref|A}}
 | [[Revolutionary socialism]]{{cref|B}}
}}
| position         = [[Left-wing politics|Left-wing]]<ref name="britannica.com">{{cite web |url=https://www.britannica.com/topic/Social-Democratic-Party-of-Japan |title=Social Democratic Party of Japan &#124; political party, Japan |website=[[Encyclopædia Britannica Online]] |publisher=[[Encyclopædia Britannica, Inc.]] |access-date=22 November 2020}}</ref><ref name="LDP JSP"/><br />'''Factions:'''<br />[[Centre-left]]{{cref|A}} to [[far-left]]{{cref|B}}
| colors           = {{color box|{{party color|Japan Socialist Party}}}} Blue
| international    = [[Socialist International]]<ref>{{cite book |last1=Docherty |first1=James C. |last2=Lamb |first2=Peter |year=2006 |title=Historical Dictionary of Socialism |url=https://books.google.com/books?id=JRYjU-L4F7wC&pg=PA186 |series=Historical Dictionaries of Religions, Philosophies, and Movements Series |edition=2nd |publisher=The Scarecrow Press |page=186 |isbn=978-0-8108-5560-1 |access-date=22 November 2020}}</ref>
| flag             = Flag of the Japan Socialist Party.svg
| footnotes        = {{cnote|A|[[Right Socialist Party of Japan]]}}{{cnote|B|[[Left Socialist Party of Japan]]}}
| country          = Japan
}}

The {{Nihongo|'''Japan Socialist Party'''|日本社会党|Nihon Shakai-tō|extra='''JSP'''}} was a major [[socialist]] and [[Progressivism|progressive]]<ref name="LDP JSP"/> political party in Japan which existed from 1945 to 1996. The party was the largest representative of the Japanese left for most of its existence and the main opponent of the right-wing [[Liberal Democratic Party (Japan)|Liberal Democratic Party]].<ref name="LDP JSP">{{cite book|editor=Akito Okada |title=Japan's School Curriculum for The 2020s: Politics, Policy, and Pedagogy |quote=Generally speaking, the LDP is a conservative party spanning the right-wing, while the JSP was a left-wing, progressive party. |date=2022 |page=14 |publisher=Springer Nature |isbn=9789811920769}}</ref>

The JSP was founded in 1945 by members of pre-war [[Proletarian parties in Japan, 1925–1932|proletarian parties]], including the [[Shakai Taishūtō]]. In the [[1947 Japanese general election|1947 election]], the JSP became the largest party in the [[National Diet]] and formed a government under [[Tetsu Katayama]] until 1948. From 1951 to 1955, the JSP was split into the [[Left Socialist Party of Japan|Left Socialist Party]] and the [[Right Socialist Party of Japan|Right Socialist Party]], and in 1960 some of its members broke away to form the rival [[Democratic Socialist Party (Japan)|Democratic Socialist Party]]. In 1955, Japan's two major [[conservative]] parties merged to form the Liberal Democratic Party (LDP), which has held power near-continuously since. The JSP was the largest opposition party for the next 40 years, but was incapable of forming a government. Nonetheless, it managed to hold about one third of the seats in the [[National Diet]] during this period, preventing the LDP from revising the [[Constitution of Japan]].<ref name="Micropædia">{{cite web |url=https://kotobank.jp/word/%E6%97%A5%E6%9C%AC%E7%A4%BE%E4%BC%9A%E5%85%9A-110180#E3.83.96.E3.83.AA.E3.82.BF.E3.83.8B.E3.82.AB.E5.9B.BD.E9.9A.9B.E5.A4.A7.E7.99.BE.E7.A7.91.E4.BA.8B.E5.85.B8.20.E5.B0.8F.E9.A0.85.E7.9B.AE.E4.BA.8B.E5.85.B8 |script-title=ja:ブリタニカ国際大百科事典 小項目事典の解説 |trans-title=The ''Encyclopædia Britannica: Micropædia''{{'}}s explanation |access-date=22 November 2020 |website=kotobank.jp |publisher=[[The Asahi Shimbun Company]] |language=ja}}</ref><ref name="Taguchi">{{cite web |last=Taguchi |first=Fukuji |url=https://kotobank.jp/word/%E6%97%A5%E6%9C%AC%E7%A4%BE%E4%BC%9A%E5%85%9A-110180#E6.97.A5.E6.9C.AC.E5.A4.A7.E7.99.BE.E7.A7.91.E5.85.A8.E6.9B.B8.28.E3.83.8B.E3.83.83.E3.83.9D.E3.83.8B.E3.82.AB.29 |script-title=ja:日本大百科全書(ニッポニカ)の解説 |access-date=19 November 2020 |trans-title=The ''Nihon Dai Hyakka Zensho: Nipponica''{{'}}s explanation |website=kotobank.jp |publisher=[[The Asahi Shimbun Company]] |language=ja}}</ref><ref name="Saito2019">{{cite book|author=Ken Saito|title=圖說日本大事記：1945–2017，改變與形塑現代日本的百大事件|url=https://books.google.com/books?id=02HLDwAAQBAJ&pg=PA50|year=2019|publisher=麥浩斯|isbn=978-986-408-463-0|page=50}}</ref>

Under the leadership of [[Takako Doi]], the JSP achieved brief resurgence in the 1990 election before losing many of its seats in the 1993 election. In 1994, JSP leader [[Tomiichi Murayama]] became prime minister of a coalition government before the coalition collapsed in 1996. The JSP's period in the government alienated many of its traditional supporters, and it was reconstituted in 1996 as the [[Social Democratic Party (Japan)|Social Democratic Party]], which became a [[minor party]]. The [[Democratic Party of Japan]] replaced the JSP as the main opposition to the LDP.

==History==
===Foundation===
{{multiple image
| align         = right
| caption_align = center
| total_width   = 300
| image1        = NISHIO Suehiro.jpg
| alt1          = Photograph of Suehiro Nishio
| caption1      = [[Suehiro Nishio]]
| image2        = 片山哲.jpg
| alt2          = Photograph of Tetsu Katayama
| caption2      = [[Tetsu Katayama]]
| footer        = [[Suehiro Nishio]] and [[Tetsu Katayama]] were among the founders of the Japan Socialist Party and held leadership positions within it. Katayama served as [[Prime Minister of Japan]] from 1947 to 1948. Nishio broke away from the party in 1960, and formed the [[Democratic Socialist Party (Japan)|Democratic Socialist Party]].
}}

The two major left-wing political parties in Japan in the 1930s were the [[Labour-Farmer Masses Party]] and [[Social Democratic Party (Japan, 1926)|Social Democratic Party]]. They merged into the [[Shakai Taishūtō]] in 1932, and were the third-largest party in the after the [[1937 Japanese general election|1937 election]]. It was dissolved in 1940 due to the [[Imperial Rule Assistance Association]].{{sfn|Cole|Totten|Uyehara|1966|pp=7-8}}

[[Suehiro Nishio]] started talking about creating a new socialist party with Chōzaburō Mizutani and [[Komakichi Matsuoka]] shortly after Emperor [[Hirohito]]'s [[Hirohito surrender broadcast|surrender broadcast]]. Thirteen former members of the [[National Diet]] announced their intention to form a new party on 5 September 1945. This organization was officially formed on November 2. It was given the Japanese name ''Nihon Shakai-tō'' (Socialist Party of Japan), but given the official English name of Social Democratic Party of Japan.{{sfn|Cole|Totten|Uyehara|1966|pp=3-4}}

An inaugural committee of 25 members was formed. The founding convention was chaired by [[Tetsu Katayama]] and Nishio was elected General Secretary. Nishio, Mizutani, and other inaugural committee members were appointed to the party's executive committee.{{sfn|Cole|Totten|Uyehara|1966|pp=4}}

===Katayama government===
The [[Japanese Communist Party]] (JCP), unbanned and its leaders freed from prison in October 1945, asked the JSP to form a common political front of Japan's democratic parties. The JSP declined stating that neither had formally established their parties or policies yet. The JSP believed that the coalition would aid the party, but did not believe that the JSP was organized enough to maintain control over it. [[Morito Tatsuo]] proposed the creation of a Democratic League for National Salvation after the [[1946 Japanese general election|1946 election]] so that the JSP could establish itself as the leader.{{sfn|Cole|Totten|Uyehara|1966|pp=10-11}} The JSP's Central Executive Committee voted to end negotiations with the JCP on 14 July 1946.{{sfn|Cole|Totten|Uyehara|1966|pp=113}}

The JSP initially selected a limited amount of candidates for the 1946 elections. However, the party drastically increased its candidate amount after the Purge Directive, issued on 4 January 1946, greatly reduced the membership of right-wing parties. Conservatives attempted to form a government with right-wing members of the JSP, but the [[Liberal Party (Japan, 1945)|Liberal Party]] and JSP were unable to.{{sfn|Cole|Totten|Uyehara|1966|pp=12-13}}

The JSP rejected an offer from the JCP to work together in the [[1947 Japanese general election|1947 election]]. The JSP became the largest party in the election with 143 seats.{{sfn|Cole|Totten|Uyehara|1966|pp=15}} It formed a coalition government under Katayama with the [[Democratic Party (Japan, 1947)|Democratic Party]] and the [[Citizens' Cooperation Party]]. Katayama was the first socialist to lead Japan.{{sfn|Cole|Totten|Uyehara|1966|pp=17}} Katayama's coalition fell in February 1948, in large part due to inexperience and subsequent poor performance in leading the government.<ref>{{cite journal |last1=Lee|first1=Yong Wook|title=The Origin of One Party Domination: America's Reverse Course and the Emergence of the Liberal Democratic Party in Japan|url=https://www.jstor.org/stable/23258199|journal=The Journal of East Asian Affairs|year=2004|volume= 18|issue=2|pages=388|jstor=23258199|access-date=26 January 2021}}</ref> A new cabinet was formed under the leadership of [[Hitoshi Ashida]], a member of the Democrats. Ashida's tenure was marked by [[Shuntō|labor disputes]] and he resigned after eight months due to a corruption scandal. A caretaker government was formed under the leadership of [[Shigeru Yoshida]].{{sfn|Cole|Totten|Uyehara|1966|pp=22-25}} Nishio, who was involved in the corruption scandal and arrested, was expelled from the JSP, but later readmitted into the right-wing JSP in 1952.{{sfn|Cole|Totten|Uyehara|1966|pp=256-257}}

Members of [[Hisao Kuroda]]'s JSP faction in the Diet were expelled after voting against the budget during Ashida's tenure. Kuroda and his supporters broke away and formed the [[Labourers and Farmers Party]]. The JSP attempted to delay the [[1949 Japanese general election|1949 election]] as it feared massive losses. The JSP's seat total fell from 148 to 48.{{sfn|Cole|Totten|Uyehara|1966|pp=24}} The JSP rejected efforts by the [[Sanbetsu]] to form a united opposition of the JSP, JCP, and Labourers and Farmers against Yoshida's government.{{sfn|Cole|Totten|Uyehara|1966|pp=114}} JSP members who left to form the Labourers and Farmers Party were readmitted in 1957.{{sfn|Cole|Totten|Uyehara|1966|pp=257}}

In the period immediately following the end of World War II, the JSP had played a key role in the drafting of the new Japanese constitution, adding progressive articles related to issues such as health, welfare and working conditions.<ref>{{cite book|url=https://books.google.com/books?id=Ba5hXsfeyhMC&q=Japan+Civil+Code+july+1947+equal+rights&pg=PA289|title=Allied Occupation of Japan|access-date=12 July 2015|url-status=live|archive-url=https://web.archive.org/web/20180503141629/https://books.google.co.uk/books?id=Ba5hXsfeyhMC&pg=PA289&dq=Japan+Civil+Code+july+1947+equal+rights&hl=en&sa=X&ei=vJgXUZrZBuWa0QWfkYDQDw&ved=0CFAQ6AEwBg#v=onepage&q=Japan%20Civil%20Code%20july%201947%20equal%20rights&f=false|archive-date=3 May 2018|isbn=9780826415219|last1=Takemae|first1=Eiji|date=January 2003|publisher=A&C Black}}</ref> Unfortunately for the JSP and the broader Japanese left in the immediate postwar era, their time in power coincided with a change in U.S. policy towards Japan commonly known as the [[Reverse Course]].<ref>{{cite web|url=https://history.state.gov/milestones/1945-1952/japan-reconstruction|title=Occupation and Reconstruction of Japan, 1945–52|access-date=26 January 2021|quote=By late 1947 and early 1948, the emergence of an economic crisis in Japan alongside concerns about the spread of communism sparked a reconsideration of occupation policies. This period is sometimes called the 'reverse course.'}}</ref> Beginning around 1947, and intensifying with the victory of the [[Chinese Communist Party|Communists]] over the [[Kuomintang|Nationalists]] in the [[Chinese Civil War]] in 1949, the U.S. occupation government headed by [[Douglas MacArthur]] felt the need to revise its previously conciliatory stance towards the kinds of policies pursued by Japanese leftists, from the breakup of [[Zaibatsu]], the country's business conglomerates, to land reform, to the ousting of nationalist figures in government.<ref>{{cite book|last=Schonberger|first=Howard B.|date=1989|title=Aftermath of War: Americans and the Remaking of Japan, 1945–1952|location=Kent, Ohio|publisher=The Kent State University Press|pages=64–72|isbn=0-87338-382-6}}</ref> Apart from reversing early steps taken towards implementing these policies, the U.S. occupation government oversaw and assisted in the purging of almost 30,000 workers deemed to be "[[Red (politics)|red]]" between 1948 and 1950, frustrating leftist attempts to hold on to state power.<ref>{{cite journal|last1=Dower|first1=John W.|last2=Hirata|first2=Tetsuo|title=Japan's Red Purge: Lessons from a Saga of Suppression of Free Speech and Thought|url=https://apjjf.org/-John-W.-Dower/2462/article.html|journal=The Asia-Pacific Journal|volume=5|issue=7|pages=3|access-date=26 January 2021}}</ref>

===Fracture and reunification===
{{multiple image
| align         = right
| caption_align = center
| total_width   = 300
| image1        = Suzuki Mosaburo.JPG
| alt1          = Photograph of Mosaburō Suzuki
| caption1      = [[Mosaburō Suzuki]]
| image2        = Inejiro Asanuma Salvaged.jpg
| alt2          = Photograph of Inejirō Asanuma
| caption2      = [[Inejirō Asanuma]]
| footer        = In 1960, the JSP broke apart into the [[Left Socialist Party of Japan]] and [[Right Socialist Party of Japan]], led by [[Mosaburō Suzuki]] and [[Inejirō Asanuma]], respectively.
}}

The party's 1949 convention was postponed until after the year's election. The party leadership, including multiple members of the Central Executive Committee, resigned following the party's defeat. The party's right-wing wanted to rename the organization to the Social Democratic Party while the left-wing wanted to retain its name, which was approved. The left-wing wanted the entire right-wing leadership to resign, Katayama retained as chairman, and [[Mosaburō Suzuki]] appointed as Secretary General. [[Inejirō Asanuma]] was the right-wing candidate for Secretary General. Asanuma defeated Suzuki in the nominating committee's vote with 31 to 30, but lost the convention vote 390 to 261. Katayama was reelected as chairman.{{sfn|Cole|Totten|Uyehara|1966|pp=26-29}}

By the time of the 1950 convention the party's factions formed two youth leagues. The left-wing controlled the official Youth Department while the right-wing formed the Independent Youth League. The Youth Department, which held its convention before the party's, demanded the expulsion of all members of the Independent Youth League and prepared a [[motion of no confidence]] against Katayama. The left-wing held greater control over the convention than in the previous year, holding almost all of the committee chairmanships. Katayama declined to run for reelection and the right-wing walked out of the convention.{{sfn|Cole|Totten|Uyehara|1966|pp=29-30}}

Members of the Diet who were not aligned with either faction formed the Unification Discussion Group. The two factions held separate conventions, but worked together in the Diet due to spring labor disputes and threats from the [[National Railway Workers' Union]] to pull its support for the party. The three groups reunited on 3 April, after three months of negation. The position of chairman was left vacant, but Asanuma was made Secretary General. The Central Executive Committee was divided between fifteen left-wingers, nine right-wingers, and six centrists.{{sfn|Cole|Totten|Uyehara|1966|pp=30}}

In the 1950 elections the JSP won the governorship of [[Kyoto Prefecture]] and became the second-largest party in the [[1950 Japanese House of Councillors election|House of Councillors]] while the JCP declined in strength.{{sfn|Cole|Totten|Uyehara|1966|pp=32}} The party's factions were heavily divided over the [[Treaty of San Francisco]] and [[Treaty of Mutual Cooperation and Security between the United States and Japan]]. The party's convention was held on 23 October 1951, and divided into the [[Right Socialist Party of Japan]] and [[Left Socialist Party of Japan]] after seventeen hours. In the Diet the left-wing voted against both treaties while the right-wing opposed the peace treaty and supported the security treaty.{{sfn|Cole|Totten|Uyehara|1966|pp=34-36}} The party remained united at the prefecture level until the final prefecture division in 1953.{{sfn|Cole|Totten|Uyehara|1966|pp=51}}

The Left Socialists selected Suzuki as chairman and Masaru Nomizo as Secretary General while the Right Socialists selected Asanuma as Secretary General and left the position of chairman vacant.{{sfn|Cole|Totten|Uyehara|1966|pp=38}} At the time of the schism the JSP's House of Representatives membership was divided into 30 Right Socialists and 16 Left Socialists. Their seat totals rose to 57 for the Right Socialists and 54 for the Left Socialists after the [[1952 Japanese general election|1952 election]].{{sfn|Cole|Totten|Uyehara|1966|pp=40-41}} Despite this divided membership the two groups worked together in the Diet with [[Kaishintō]] and disaffected Liberals to pass motions of no confidence against Minister of Finance [[Hayato Ikeda]].{{sfn|Cole|Totten|Uyehara|1966|pp=43}}

In 1953, Yoshida lost a vote of no confidence to the socialists and conservatives after disaffected Liberals abstained and new elections were called. The Left Socialists overtook the Right Socialists in seat count in the [[1953 Japanese general election|general election]]. In the [[1953 Japanese House of Councillors election|House of Councillors election]] the Left Socialists rose from 30 to 41 seats while the Right Socialists declined from 30 to 26 seats. The Right Socialists attempted to form a coalition with the Left Socialists, Kaishintō, and disaffected Liberals. This failed as [[Minoru Takano]] failed to convince the Left Socialists, who wanted Suzuki as prime minister, to accept [[Mamoru Shigemitsu]], the Kaishintō leader, as prime minister. Yoshida became prime minister again after two ballots and Kaishintō announced that it would end its partnership with the socialists.{{sfn|Cole|Totten|Uyehara|1966|pp=44-45}}

{|class="wikitable floatright" style="border:1px black; float:right; margin-left:1em;"
|+ colspan="2"|Factions in the JSP in 1959{{sfn|Cole|Totten|Uyehara|1966|pp=276-277}}
|-
!Leader
!Ideology
!House of Representatives
!House of Councillors
|-
![[Suehiro Nishio]]
|Right-wing
|{{Composition bar|27|467|hex={{party color|Japan Socialist Party}}}}
|{{Composition bar|17|250|hex={{party color|Japan Socialist Party}}}}
|-
![[Jōtarō Kawakami]]
|Right-wing
|{{Composition bar|29|467|hex={{party color|Japan Socialist Party}}}}
|{{Composition bar|10|250|hex={{party color|Japan Socialist Party}}}}
|-
![[Mosaburō Suzuki]]
|Left-wing
|{{Composition bar|39|467|hex={{party color|Japan Socialist Party}}}}
|{{Composition bar|20|250|hex={{party color|Japan Socialist Party}}}}
|-
!Hiroo Wada
|Left-wing
|{{Composition bar|29|467|hex={{party color|Japan Socialist Party}}}}
|{{Composition bar|10|250|hex={{party color|Japan Socialist Party}}}}
|-
![[Jiichirō Matsumoto]]
|Left-wing
|{{Composition bar|12|467|hex={{party color|Japan Socialist Party}}}}
|{{Composition bar|0|250|hex={{party color|Japan Socialist Party}}}}
|-
!Masaru Nomizo
|Left-wing
|{{Composition bar|5|467|hex={{party color|Japan Socialist Party}}}}
|{{Composition bar|15|250|hex={{party color|Japan Socialist Party}}}}
|-
!Hisao Kuroda
|Left-wing
|{{Composition bar|6|467|hex={{party color|Japan Socialist Party}}}}
|{{Composition bar|0|250|hex={{party color|Japan Socialist Party}}}}
|}

Yoshida lost a motion of no confidence supported by the [[Japan Democratic Party]] and Socialists on 7 December 1954. [[Ichirō Hatoyama]] replaced him and [[1955 Japanese general election|new elections]] were called. The Left and Right Socialists, faced with Hatoyama's popularity, adopted the same platform. The two groups held conventions on 18 January 1955, in which they called to reunify after the election. The combined Socialist seat total, 156, was greater than their seat total during Katayama's government. Unification negotiation committees met in April and the platform it created was accepted by a united convention on 13 October. Suzuki was appointed as chairman and Asanuma as Secretary General. The Central Executive Committee and Control Commission was divided equally between the two factions.{{sfn|Cole|Totten|Uyehara|1966|pp=48-50; 53-55}} The left-wing gained a 22 to 18 seat majority on the Central Executive Committee at the 1957 convention.{{sfn|Cole|Totten|Uyehara|1966|pp=59-60}}

The JSP made minor gains in the [[1958 Japanese general election|1958 general election]] and [[1959 Japanese House of Councillors election|1959 House of Councillors election]]. It performed poorly in the 1959 gubernatorial election, including the loss of the [[List of governors of Hokkaido Prefecture|governorship]] of [[Hokkaido]]. The JSP was harmed as the JCP, which had strategically withdrawn its candidates in other elections, declined to do so in the 1958 and 1959 elections.{{sfn|Cole|Totten|Uyehara|1966|pp=65; 69-70}}

===Divisions and Asanuma's assassination===

The party split again in 1960 because of internal disagreement over how to conduct the ongoing [[Anpo protests]] against revision of the security treaty and whether or not to cooperate with the JCP in doing so.{{sfn|Kapur|2018|pp=109–112}} Left-wingers from [[Sōhyō]] and the Youth Division, with backing from supporters of Hiroo Wada and [[Jiichirō Matsumoto]], had attempted to expel Nishio at the 1959 convention, but it failed in the Steering Committee. Nishio attacked the left-wing for serving Sōhyō. The Association for Party Reconstruction, which called for "democratic socialism" that received support from "the whole nation, not merely the labor unions and farmers' organizations", held a convention attended by 300 right-wing leaders and 28 Diet members. The Socialist Club, under the leadership of Nishio, had 12 members in the House of Councillors and 21 in the House of Representatives. This organization broke away to form the [[Democratic Socialist Party (Japan)|Democratic Socialist Party]] (DSP) on 24 January 1960.{{sfn|Cole|Totten|Uyehara|1966|pp=73-75}}
[[Image:Tokyo Stabbing.jpg|thumb|300px|Pulitzer Prize-winning photograph by [[Yasushi Nagao]]. The photo was taken directly after Yamaguchi stabbed Asanuma and is here seen attempting a second stab, although he was restrained before that could happen.]]
Asanuma was elected chairman of the JSP at the 1960 convention.{{sfn|Cole|Totten|Uyehara|1966|pp=75}} Asanuma was assassinated by a right-wing youth, [[Otoya Yamaguchi]], during a televised election debate on 12 October 1960.{{sfn|Kapur|2018|p=127}} Asanuma had been a charismatic figure who had been able to hold the antagonistic left and right factions of the party together through the force of his personality.{{sfn|Kapur|2018|p=127}} Asanuma's untimely death deprived the party of his adroit leadership, and thrust [[Saburō Eda]] into the leadership role instead.{{sfn|Kapur|2018|p=127}} Eda was hastily named "Acting Chairman" of the JSP and became the party's leader and candidate to become prime minister of Japan should the party triumph in the election. A centrist, Eda rapidly took the party in a more centrist direction, far faster than the left socialists were ready to accept.{{sfn|Kapur|2018|p=127}} This led to growing infighting within the party, and drastically damaged its ability to present a cohesive message to the public.{{sfn|Kapur|2018|pp=121–126}}

In particular, Eda earned the enmity of the party's left-wing due to his ambitious platform of {{Nihongo|"structural reform"|構造改革|kōzō kaikaku}} and his related "Eda Vision" of socialism.{{sfn|Kapur|2018|p=114}} The "structural reform" platform drew inspiration from the recently concluded [[Anpo protests]] against the [[U.S.-Japan Security Treaty]], which had achieved massive size and forced the resignation of conservative prime minister [[Nobusuke Kishi]]. Eda and his allies viewed these protests as having been an unalloyed success in having allowed the JSP to play a leading role in fomenting a mass movement. Eda's "structural reform" platform called for a combination of parliamentary pressure tactics and Anpo-style extra-parliamentary mass movements that would gradually move Japan toward socialism by forcing the government into a series of piecemeal concessions.{{sfn|Kapur|2018|pp=116–121}} Above all, Eda and his fellow structural reformers hoped to broaden the base of the JSP beyond a hard core of labor unionists, leftist student activists, and Marxist intellectuals to encompass people from many walks of life, in order to dramatically increase the party's potential supporters at the polls.{{sfn|Kapur|2018|pp=118}}

In an effort to build popular support for his reform program, Eda announced his "New Vision of Socialism", better known by its nickname, the "Eda Vision", in July 1962.{{sfn|Kapur|2018|pp=124}} Eda declared that "[s]ocialism must be defined in sunny and cheerful terms that are easily understandable to the masses. I believe that 'socialism' is that which allows human potential to blossom to its fullest extent. The main four accomplishments that humankind has achieved so far are America's high standard of living, the Soviet Union's thoroughgoing social welfare system, England's parliamentary democracy, and Japan's peace constitution. I believe that if we can integrate these, we can give birth to a broad-based socialism."{{sfn|Kapur|2018|pp=124}}

The "Eda Vision" of a more moderate form of socialism was received enthusiastically in the mainstream Japanese press, and polled well in public opinion polls.{{sfn|Kapur|2018|pp=124}} However, it did not lead to any significant expansion of party membership; in 1961, the JSP made a push to increase its membership to over 100,000 within the next three years, but only 363 members were added over the next six months.{{sfn|Cole|Totten|Uyehara|1966|pp=246}} Moreover, the "Eda Vision" was the final straw for the more [[orthodox Marxist]] left-wing factions in the JSP, who had already chafed against the moderate tone of Eda's "structural reform" platform. In particular, they could not accept praise of what they viewed as the "imperialist" United States and Great Britain, and the "deviationist" and "Stalinist" Soviet Union.{{sfn|Kapur|2018|p=125}} At the 22nd Party Congress in November 1962, the left-wing of the JSP revolted, and succeeded in persuading a majority of party members present to adopt an "Eda Vision Criticism Resolution" that renounced the "Eda Vision" as antithetical to core party principles.{{sfn|Kapur|2018|p=125}} Eda was forced to resign his position as Secretary General, and thereafter the party returned to a more dogmatically Marxist platform which emphasized the urban working classes as the party's main political base.{{sfn|Kapur|2018|p=125}}

Thereafter, a younger generation of reform-minded activists became disillusioned and began to drift away from the party.{{sfn|Kapur|2018|p=125}} At the same time, the emergence of the "[[Kōmeitō|Clean Government Party]]" (''Kōmeitō''), the political wing of the [[Sokka Gakkai]] Buddhist religious movement, and the increasing electoral success of the [[Japan Communist Party]], began to eat away at the JSP's urban working class base.{{sfn|Kapur|2018|p=125}} The Socialists slipped in the polls in the 1967 election, lost more ground in the 1968 Upper House election, and suffered a crushing repudiation in 1969, when they lost 51 seats in the [[National Diet]].{{sfn|Kapur|2018|pp=125–126}}

===1970s===
In some regions, the party continued to perform well at the local level and by the 1970s many areas were run by JSP (or JSP-backed) mayors and governors, who supported environmental protection initiatives and introduced new social welfare programs.<ref>{{cite web |last=MacDougall |first=Terry |url=http://siteresources.worldbank.org/WBI/Resources/wbi37169.pdf |title=Towards Political Inclusiveness: The Changing Role of Local Government in Japan |pages=11 |year=2001 |website=The World Bank Institute |access-date=20 April 2012 |url-status=dead |archive-url=https://web.archive.org/web/20121202102136/http://siteresources.worldbank.org/WBI/Resources/wbi37169.pdf |archive-date=2 December 2012}}</ref><ref>{{cite book|url=https://books.google.com/books?id=g7DdQriL824C|title=Cities, Autonomy, and Decentralization in Japan|access-date=12 July 2015|url-status=live|archive-url=https://web.archive.org/web/20161127024014/https://books.google.co.uk/books?id=g7DdQriL824C&pg=PA131&dq=Ryokichi+Minobe+public+housing&hl=en&sa=X&ei=i2eQT7yzLOnG0QXYyKTlAQ&ved=0CE8Q6AEwBQ#v=onepage&q=Ryokichi%20Minobe%20public%20housing&f=false|archive-date=27 November 2016|isbn=9781134341504|last1=Hein|first1=Carola|last2=Pelletier|first2=Philippe|year=2006|pages=131|publisher=Routledge}}</ref><ref>{{cite book|url=https://books.google.com/books?id=IECgEbopHo8C|title=Local Government Development in Post-war Japan|pages=51|isbn=9780199248285|last1=Muramatsu|first1=Michio|last2=Iqbal|first2=Farrukh|last3=Kume|first3=Ikuo|year=2001|publisher=Oxford University Press}}</ref><ref>{{cite book|url=https://books.google.com/books?id=gdwEocAa3nYC|title=Routledge Handbook of Japanese Politics|access-date=12 July 2015|url-status=live|archive-url=https://web.archive.org/web/20161127024330/https://books.google.co.uk/books?id=gdwEocAa3nYC&pg=PA107&dq=japan+progressive+governors+socialists&hl=en&sa=X&ei=s0YFUrTwB66S0QWrl4HoCw&ved=0CEMQ6AEwAw#v=onepage&q=japan%20progressive%20governors%20socialists&f=false|archive-date=27 November 2016|isbn=9781136818387|last1=Gaunder|first1=Alisa|date=25 February 2011|publisher=Taylor & Francis}}</ref><ref>{{cite web|url=http://www.thefreelibrary.com/FEATURE%3A+Seeds+planted+by+'progressive'+governments+still+sprouting...-a0155748826|title=FEATURE: Seeds planted by 'progressive' governments still sprouting in Japan.|access-date=12 July 2015}}</ref><ref>{{cite web |url=http://unpan1.un.org/intradoc/groups/public/documents/APCITY/UNPAN019274.pdf |title=Controlled Decentralization: Local Governments and the Ministry of Home Affairs in Japan|access-date=10 August 2013 |url-status=live |archive-url=https://web.archive.org/web/20150712232935/http://unpan1.un.org/intradoc/groups/public/documents/APCITY/UNPAN019274.pdf |archive-date=12 July 2015}}</ref><ref>{{cite book|url=https://books.google.com/books?id=2GdKF8ozQOIC&q=japan+socialist+governors+1970%27s&pg=PA410|title=The Pursuit of Power in Modern Japan 1825–1995|access-date=12 July 2015|url-status=live|archive-url=https://web.archive.org/web/20180503141629/https://books.google.co.uk/books?id=2GdKF8ozQOIC&pg=PA410&dq=japan+socialist+governors+1970's&hl=en&sa=X&ei=mB0GUrzDBsXa0QWdmoDoBA&ved=0CEcQ6AEwBA#v=onepage&q=japan%20socialist%20governors%201970's&f=false|archive-date=3 May 2018|isbn=9780191542459|last1=Tsuzuki|first1=Chushichi|date=13 April 2000|publisher=OUP Oxford}}</ref>

Meanwhile, [[Saburō Eda]] continued his efforts to reform the party and expand its base. Eda ran numerous times for the post of party chairman, but was unsuccessful, although he did serve a second stint as Secretary General from 1968 to 1970.  Nevertheless, Eda remained popular among the broader Japanese public and in the mid-1970s conservative prime minister [[Kakuei Tanaka]] said at a press conference, "If the Japan Socialist Party were ever to make Eda its Chairman again, a general election would be terrifying. They would drastically expand their seats in the Diet."<ref>{{Cite book|author=福岡義登|editor=日本社会党前議員会|url=https://books.google.com/books?id=xlo6AAAAMAAJ|title=日本社会党歴代委員長の思い出: 亡くなられた委員長をしのぶ|publisher=日本社会党前議員会|year=1985|chapter=江田三郎先生を偲んで|pages=319}}</ref> Eda could never overcome the undying animosity his "Eda Vision" had won him from his party's left-wing.{{citation needed|date=August 2021}}

In 1976, Eda lost his reelection bid and was booted from the Diet. Blaming his loss on his party's dogmatic, doctrinaire Marxism and desperate for reform, he attempted to resign from the JSP but the party refused to accept his resignation and voted to expel him instead. The following year, Eda and [[Hideo Den]] ({{Nihongo2|田英夫}}) led a small group of JSP Dietmembers to split from the JSP and form a new party called the [[Socialist Democratic Federation (Japan)|Socialist Democratic Federation]] ({{Nihongo2|社会民主連合}}).<ref>{{cite web|url=https://kotobank.jp/word/%E7%A4%BE%E4%BC%9A%E6%B0%91%E4%B8%BB%E9%80%A3%E5%90%88-75726|script-title=ja:社会民主連合|website=朝日新聞社Kotobank|access-date=26 February 2020|archive-url=https://web.archive.org/web/20200226092340/https://kotobank.jp/word/%E7%A4%BE%E4%BC%9A%E6%B0%91%E4%B8%BB%E9%80%A3%E5%90%88-75726|archive-date=26 February 2020}}</ref><ref>{{cite web|url=https://kotobank.jp/word/%E6%B1%9F%E7%94%B0%E4%B8%89%E9%83%8E-36660|script-title=ja:江田三郎|website=朝日新聞社Kotobank|access-date=26 February 2020|archive-url=https://web.archive.org/web/20200226092342/https://kotobank.jp/word/%E6%B1%9F%E7%94%B0%E4%B8%89%E9%83%8E-36660|archive-date=26 February 2020}}</ref>

===1980s===
[[File:Headquarters of the Social Democratic Party of Japan (2009.09 3).jpg|thumb|250px|Former JSP Head Office in [[Nagatacho]], the Social & Cultural Center ({{Nihongo2|社会文化会館}})]]

In July 1986, under party chairman [[Masashi Ishibashi]], the JSP suffered a disastrous double defeat in both houses of the [[National Diet]] in the simultaneously held [[1986 Japanese general election]] and [[1986 Japanese House of Councillors election]]. Losing in a rout to the [[Liberal Democratic Party (Japan)|Liberal Democratic Party]] (LDP) under popular prime minister [[Yasuhiro Nakasone]], the JSP's seats in the lower house fell from 112 to a new all-time low of 85 and its share of the popular vote dropped from 19.5 percent to 17.2 percent. This defeat led the party to elect [[Takako Doi]] as party chair, making her the first woman to ever lead a Japanese political party. Doi was popular with the Japanese public led the JSP to an electoral comeback with an impressive showing in the [[1990 Japanese general election]], winning 136 seats and 24.4 percent of the vote. Some electoral districts had more than one successful socialist candidate. Doi's decision to put up more than one candidate for each of the 130 districts represented a controversial break with the past because unlike their LDP counterparts many party candidates did not want to run against each other; however, the great majority of the 149 socialist candidates who ran were successful, including seven of eight women.{{citation needed|date=August 2021}}

Doi, a university professor of constitutional law before entering politics, had a tough, straight-talking manner that appealed to voters tired of the evasiveness of other politicians. Many women found her a refreshing alternative to submissive female stereotypes and in the late 1980s the public at large in opinion polls voted her their favorite politician (the runner-up in these surveys was equally tough-talking conservative LDP member [[Shintarō Ishihara]]); however, Doi's popularity was of limited aid to the party, as the powerful Shakaishugi Kyokai (Japan Socialist Association), which was supported by a contingent of the party's 76,000-strong membership, remained committed to orthodox Marxism, impeding Doi's efforts to promote what she called ''[[perestroika]]'' and a more moderate program with greater voter appeal.{{citation needed|date=August 2021}}

In 1983, Doi's predecessor as chairman [[Masashi Ishibashi]] had begun the delicate process of moving the party away from its strong opposition to the [[Japan Self-Defense Forces|Self-Defense Forces]]. While maintaining that these forces were unconstitutional in light of [[Article 9 of the Constitution of Japan|Article 9]], he claimed that because they had been established through legal procedures, they had a legitimate status (this phrasing was changed a year later to say that the Self-Defense Forces exist legally). Ishibashi also broke past precedent by visiting Washington to talk with United States political leaders. By the end of the decade, the party had accepted the Self-Defense Forces and the 1960 [[Treaty of Mutual Cooperation and Security Between the United States and Japan|U.S.-Japan Security Treaty]]. It advocated strict limitations on military spending (no more than 1 percent of GNP annually), a suspension of joint military exercises with United States forces, and a reaffirmation of the three non-nuclear principles (no production, possession, or introduction of nuclear weapons into Japanese territory).{{citation needed|date=August 2021}}

Doi expressed support for balanced ties with the Democratic People's Republic of Korea ([[North Korea]]) and the Republic of Korea ([[South Korea]]). In the past, the party had favored the [[Kim Il Sung]] regime in [[Pyongyang]] and in the early 1990s it still refused to recognize the normalization of relations between Tokyo and Seoul with [[Treaty on Basic Relations between Japan and the Republic of Korea]] (1965). In domestic policy, the party demanded the continued protection of agriculture and small business in the face of foreign pressure, abolition of the [[consumption tax]] and an end to the construction and use of nuclear power reactors. As a symbolic gesture to reflect its new moderation, the party dropped its commitment to [[revolutionary socialism|socialist revolution]] at its April 1990 convention and described its goal as social democracy,<ref name="Neary2012">{{cite book|author=Ian Neary|title=War, Revolution and Japan|url=https://books.google.com/books?id=Yfn7quu5sc0C&pg=PA141|access-date=29 January 2013|date=12 October 2012|publisher=Taylor & Francis|isbn=978-1-873410-08-0|pages=141–}}</ref> the creation of a society in which "all people fairly enjoy the fruits of technological advancement and modern civilization and receive the benefits of [[social welfare]]." Delegates also elected Doi to a third term as party chairwoman.{{citation needed|date=August 2021}}

Because of the party's self-definition as a class-based party and its symbiotic relationship with the [[Sōhyō|General Council of Trade Unions of Japan]] ({{lang|ja-latn|Sōhyō}}), the public-sector workers' confederation, few efforts were made to attract non-union constituencies. Although some {{lang|ja-latn|Sōhyō}} unions supported the [[Japanese Communist Party]], the party remained the representative of Sohyo's political interests until the merger with private-sector unions and the [[RENGO|Japanese Trade Union Confederation]] ({{lang|ja-latn|Rengō}}) in 1989. Because of declining union financial support during the 1980s, some party Diet members turned to dubious fund-raising methods. One was involved in the [[Recruit scandal|Recruit affair]]. Like other parties, it sold large blocks of fund-raising party tickets and the LDP even gave individual party Diet members funds from time to time to persuade them to cooperate in passing difficult legislation.{{citation needed|date=August 2021}}

=== 1990s ===
{{Main|Social Democratic Party (Japan)}}
As part of the fallout of the [[Recruit Scandal]], the party secured a mere 70 seats (down from 137) in the [[1993 Japanese general election]] while the LDP lost its majority in the lower house for the first time since the [[1983 Japanese general election]] and was out of government for the first time in 38 years. The anti-LDP [[coalition government]] of [[Morihiro Hosokawa]] was formed by reformists who had triggered the 1993 election by leaving the LDP ([[Japan Renewal Party]] and [[New Party Sakigake]]), a liberal party formed only a year before ([[Japan New Party]]), the traditional centre-left opposition ([[Kōmeitō (1962–98)|Kōmeitō]], [[Democratic Socialist Party (Japan)|Democratic Socialist Party]] and [[Socialist Democratic Federation (Japan)|Socialist Democratic Federation]]) and the Democratic Reform Party, the political arm of the {{lang|ja-latn|Rengō}} trade union federation, together with the JSP. In 1994, the JSP and the New Sakigake Party decided to leave the non-LDP coalition. The minority Hata cabinet lasted only a few weeks.{{citation needed|date=August 2021}}

The JSP then formed a [[grand coalition]] (''dai-renritsu'') government with the LDP and the New Party Sakigake under JSP Prime Minister [[Tomiichi Murayama]], who was leader of the party from 1993 to 1996. Most of the other parties from the anti-LDP coalition, now forced back into opposition, united to form the [[New Frontier Party (Japan)|New Frontier Party]] (NFP), which overtook the JSP as second largest political party in Japan. The JSP suffered a defeat in the [[1995 Japanese House of Councillors election]]. In January 1996, the [[New Socialist Party of Japan]] split off from the JSP, Murayama resigned as Prime Minister, and the JSP changed its name from the JSP to the [[Social Democratic Party (Japan)|Social Democratic Party]] (SDP) as an interim party for forming a new party.{{citation needed|date=August 2021}}

[[File:The History of Japan Socialist Party - en.png|thumb|700px|center|An illustration of the history of JSP]]

==Factions and membership==
Nomizo and his faction were affiliated with agricultural workers and unions. Their power in the JSP waned after land reforms in the 1950s. Matsumoto and his faction found support among the [[Burakumin]], whose rights Matsumoto advocated for.{{sfn|Cole|Totten|Uyehara|1966|pp=286-287}} The JSP consistently received around 10-20% of the female vote. In 1957, women were estimated to account for 10% of the JSP's membership and the party had eleven female members in the Diet.{{sfn|Cole|Totten|Uyehara|1966|pp=438-439}}

===Agriculture===
The Japan Farmers' Union was officially not aligned with any party, but its leadership were members of the JSP.{{sfn|Cole|Totten|Uyehara|1966|pp=376-377}} Five the union's seven executive members were elected to the Diet, including Kuroda and Nomizo.{{sfn|Cole|Totten|Uyehara|1966|pp=379}} Rikizō Hirano, the Minister of Agriculture and aligned with the JSP's right-wing, led 15% of the union to break away into League for Revivifying the Japan Farmers' Union (later renamed to the All-Japan Farmers' Union) after continued disputes with the left-wing and communists at the union's 1947 convention. 31 of the 143 seats won by the JSP in the 1947 election were held by officers of the Japan Farmers' Union and an additional 8 were held by members of Hirano's union.{{sfn|Cole|Totten|Uyehara|1966|pp=381-382}} Nomizo attempted to become Minister of Agriculture after Hirano's dismissal, but the right-wing successfully opposed him.{{sfn|Cole|Totten|Uyehara|1966|pp=384}}

In the face of rising communist influence in the union JSP members formed the League for the Establishment of Independence in 1948, while Kuroda and the communists formed the Unity Discussion Group. The union broke apart into the Independence Group and Unity Group as these two groups held separate conventions on 22 April 1949.{{sfn|Cole|Totten|Uyehara|1966|pp=384-385}}

New agrarian groups were formed after the JSP broke apart into the Left and Right parties. The Independence Group was aligned with the Left JSP. The Right JSP had the New Village Construction Group of the Japan Farmers' Union, but it never held a convention during its existence and was poorly organized. The All-Japan Famers' Union federated with this organization and formed the General Federation of Farmers' Union after Hirano joined the Right JSP.{{sfn|Cole|Totten|Uyehara|1966|pp=391}} A sample of 48 Left JSP and 33 Right JSP candidates in 1955 showed that 31 Left JSP candidates had farmer union support compared to 7 Right JSP candidates.{{sfn|Cole|Totten|Uyehara|1966|pp=395}} The All-Japan Farmers' Union, New Village Construction Group, a rump faction of the Independence Group unified into the National Japan Farmers' Union in 1958.{{sfn|Cole|Totten|Uyehara|1966|pp=397; 399}} Another schism occurred as supporters of Nishio left to form the All-Japan Farmers' Federation aligned with the DSP.{{sfn|Cole|Totten|Uyehara|1966|pp=401}}

===Labor===
Sōhyō, the largest labor federation in Japan, was aligned with the JSP's left-wing while the National Railway Workers' Union was aligned with the right-wing.{{sfn|Cole|Totten|Uyehara|1966|pp=333-334}} The [[Red Purge]] resulted in the amount of unions falling by 5,500 and union membership falling by 880,000 in 1949 alone. Sōhyō's membership fell to below 47,000 in this period, but grew to 3.7 million by 1962.{{sfn|Cole|Totten|Uyehara|1966|pp=331; 334}} Sōhyō had three major factions during the JSP's split in the 1950s. The left-wing Worker Comrades Society had ties to the Suzuki and Wada factions, a communist faction under [[Minoru Takano]]'s leadership, and right-wing Democratic Labor Movement Study Group. The Democratic Labor Movement Study Group broke away to form the [[All-Japan Trade Union Congress]] in April 1954.{{sfn|Cole|Totten|Uyehara|1966|pp=336-338}} 26 representatives and 38 councilors were affiliated with Sōhyō after the 1956 election.{{sfn|Cole|Totten|Uyehara|1966|pp=365}}

Polling by ''[[The Asahi Shimbun]]'' in October 1948, showed that 40% of unionized workers supported the JSP, but 18% of non-unionized workers supported them. These figures was 39% and 28% respectively in 1949, and 37% and 26% in 1950.{{sfn|Cole|Totten|Uyehara|1966|pp=366}}

==Ideology==

===Domestic===
The JSP is generally regarded as having been a progressive "[[left-wing]]" party that opposed the conservative "[[right-wing]]" [[Liberal Democratic Party (Japan)|Liberal Democratic Party]] (LDP).<ref name="LDP JSP"/> The JSP is also considered a [[centre-left]] party,<ref>{{cite book|editor1=Ralf Kleinfeld |editor2=Carmen Schmidt |url=https://books.google.com/books?id=Dxu7DwAAQBAJ&pg=PA200 |title=The Crisis of Democracy? Chances, Risks and Challenges in Japan (Asia) and Germany (Europe) |quote=After the merger of the conservative and center-left camp in 1955, and the formation of the conservative LDP and the center-left JSP (Japan Socialist Party), the LDP upheld the position of the ruling party until 1993. |date=2019 |page=200 |publisher= [[Cambridge Scholars Publishing]] |isbn=9781527542419}}</ref> but there was a far-left faction within the party.<ref>{{cite book|editor=Sandra Buckley |url=https://books.google.com/books?id=Wtkm3O3nWXkC&pg=PA544 |title=The Encyclopedia of Contemporary Japanese Culture |quote=Sanbetsu was closely tied to the Japan Communist Party and the far left wing of the Japan Socialist Party. |date=2009 |page=544 |publisher=Taylor & Francis |isbn=9780415481526}}</ref><ref>{{cite book |url=https://books.google.com/books?id=DQr2PS8RTaYC&pg=PA4 |title=Japan |quote=... Confederation) and Zenrokyo (the National Labor Union Consultative Council), were also formed, representing unions associated with the Japan Communist Party and a far-left faction of the Japan Socialist Party, respectively. |date=1989 |page=4 |publisher=U.S. Department of Labor, Bureau of International Labor Affairs}}</ref> The so-called "leftists" in the JSP were [[Marxists]] in favour of [[scientific socialism]]. By contrast, the so-called "rightists" were in favour of [[social democracy]] and aimed at establishing a [[welfare state]].<ref name="高山直人2019">{{cite book|author=高山直人|title=左翼大辞典|url=https://books.google.com/books?id=Im6VDwAAQBAJ&pg=PT7|year=2019|publisher=明哲の舎|page=7|id=GGKEY:9NSLG3F0CUC}}</ref> The party was generally the mainstay of the "[[Progressive political parties (Japan)|Kakushin]]" (radical-liberal forces) camp.<ref>{{cite book|editor=Tetsuya Kataoka |title=Creating Single-party Democracy: Japan's Postwar Political System |quote= The constitution was defended by the JSP, the mainstay of kakushin (radical-liberal forces), ... |date=1992 |page=2 |publisher=Hoover Institution Press |isbn=9780817991111}}</ref>

The JSP's foundation program in 1945 was three sentences long and stated that the party was "the national rally of the laboring strata". This program was maintained until 1955.{{sfn|Cole|Totten|Uyehara|1966|pp=86-87}} Both [[nationalization]], supported by the left-wing, and [[Socialization (Marxism)|socialization]], supported by the right-wing, were in the 1955 platform.{{sfn|Cole|Totten|Uyehara|1966|pp=106}} In the 1950s the party supported a five-year plan to socialize the electricity, coal, iron and steel, chemical fertilizer, transportation, and cement industries.{{sfn|Cole|Totten|Uyehara|1966|pp=180}} The party supported a minimum wage of {{Inflation|JP|15000|1961|fmt=eq|orig=yes|cursign=¥}} in 1961.{{sfn|Cole|Totten|Uyehara|1966|pp=194}}

After [[Takako Doi]] became party leader, the JSP established a European-style [[democratic socialism]] line.<ref>{{cite book |editor=Ardath W. Burks |title=Japan: A Postindustrial Power--third Edition, Revised And Updated |url=https://books.google.com/books?id=7iqNDwAAQBAJ&pg=PT150 |quote= After Takako Doi became party leader, the JSP established a European-style democratic socialism line. |date=2019 |publisher=[[Routledge]]|isbn=9780429718953}}</ref> Apart from the party's socialist identity, the [[Murayama Cabinet]], which came to power between 1994 and 1996, supported [[social-liberal]] reform.<ref>{{cite book|editor=Arthur Stockwin |url=https://books.google.com/books?id=G2qLEAAAQBAJ&dq=%22left+liberal%22+JSP+japan&pg=PT65 |title=The Failure of Political Opposition in Japan: Implications for Democracy and a Vision of the Future |quote=The Murayama government had a number of broadly [[left-liberal]] reforms to its credit. |date=2022 |publisher=[[Taylor & Francis]] |isbn=9789811920769}}</ref>

The JSP opposed [[Shinto]]ist [[social conservatism]], and was politically friendly with [[Christianity in the United States]]. There were quite a few Christians in the JSP. Former Japanese Prime Minister [[Tetsu Katayama]] was also a Christian.<ref>{{cite book |editor1=American Assembly |editor2=Willard Long Thorp |title=Japan's School Curriculum for The 2020s: Politics, Policy, and Pedagogy |quote= It is no accident that Japanese radical liberalism and democratic socialism were both closely connected in their beginnings with the Christian movement in Japan. The first Japanese Socialist Party was born in an Americansponsored Christian church in Tokyo, and the majority of its members were Christians with intimate American connections. |date=1964 |page=17 |publisher=Prentice-Hall}}</ref>

===Foreign===
The JSP supported a neutralist [[foreign policy]]{{sfn|Cole|Totten|Uyehara|1966|pp=200}} and opposed amending the [[Constitution of Japan]], especially the [[Article 9 of the Constitution of Japan]].<ref name="Micropædia"/><ref name="Taguchi"/> Japan's [[Classical radicalism#Japan|left-wing liberalism]] emerged as a "peace movement" and was largely led by the JSP.<ref>{{cite book |editor1=Arthur Stockwin |editor2=Kweku Ampiah |title=Rethinking Japan: The Politics of Contested Nationalism |quote=... of the debate is the left/liberal "peace movement" currently led by Japanese academics, including legal scholars, and more recently by students, but which until the end of the Cold War was spearheaded by the Japan Socialist Party. |date=2017 |page=196 |publisher=[[Lexington Books]] |isbn=9781498537933}}</ref> Suzuki stated that he wanted Japan to follow Yugoslavia's brand of neutrality rather than Austria's.{{sfn|Cole|Totten|Uyehara|1966|pp=205}} The left-wing participated in anti-American military base protests in 1953, while the right-wing did not.{{sfn|Cole|Totten|Uyehara|1966|pp=115}} The party was critical of nuclear testing done by the United States and Soviet Union.{{sfn|Cole|Totten|Uyehara|1966|pp=212-213}}

The party interacted with the [[North Korea]]'s [[Korean Social Democratic Party]].<ref>{{cite book |editor=조선사회민주당 중앙위원회 |title=조선사회민주당 |date=1992 |publisher=조선사회민주당출판사}}</ref> The party was also strongly opposed to the [[far-right]] [[South Korea]]'s [[anti-communist]] dictatorship, including [[Park Chung Hee]] and [[Chun Doo-hwan]], and allied with [[Liberalism in South Korea|South Korean liberals]], including [[Kim Dae-jung]].<ref>{{cite web | url=https://www.ohmynews.com/NWS_Web/View/at_pg.aspx?CNTN_CD=A0002767853&isPc=true |title=일본 정치인의 40분 연설 "김대중 정신 일본사회가 배워야" |website=[[OhmyNews]] | date=19 August 2021 |access-date=22 April 2023}}</ref> The JSP ended its support for the [[Two Chinas]] policy in 1957, and recognized the People's Republic of China rather than the Republic of China.{{sfn|Cole|Totten|Uyehara|1966|pp=204}}

The JSP supported [[Gamal Abdel Nasser]]'s nationalization of the [[Suez Canal]]. The party's factions were heavily divided by the [[Hungarian Revolution of 1956]], with the right-wing supported Hungary and the left-wing supporting the Soviet Union, before a compromise was made stating that "the subsequent [[de-Stalinization]] and liberalization were somewhat taken advantage of by reactionary forces, the armed intervention of the Soviet Union cannot be condoned".{{sfn|Cole|Totten|Uyehara|1966|pp=224-226}}

== Leaders ==
{|class="wikitable"  style="text-align:center"
!rowspan=2|No.
!rowspan=2|Photo
!rowspan=2|Name<br /><small>{{nowrap|(Birth–death)}} </small>
!rowspan=2|Constituency / title
!colspan=2|Term of office
!rowspan=2|Election results
! colspan="2" style="width:20%;" rowspan="2"|[[Prime Minister of Japan|{{nowrap|Prime Minister}}]] {{small|(term)}}
|-
!Took office
!Left office
|-
|colspan="9" bgcolor="lightblue"|'''Chair of the Social Democratic Party of Japan (1946–1950)'''
|-
|rowspan=4|1 || rowspan=4|[[File:片山哲.jpg|100px]] || rowspan=4|[[Tetsu Katayama]]<br /><small>{{nowrap|(1887–1978)}}</small><br />[[File:Emblem of the Prime Minister of Japan.svg|25px]] || rowspan=4|Rep for<br />Kanagawa 3rd || rowspan=4|28 September 1946 || rowspan=4|16 January 1950 || rowspan=4|—
| style="background-color: {{party color|Liberal Party (Japan, 1945)}}" |
! style="font-weight:normal"|[[Shigeru Yoshida|Yoshida]] <small>{{nowrap|1946–47}}</small>
|-
| style="background-color: {{party color|Japan Socialist Party}}" |
| ''himself'' {{small|1947–48}}
|-
| style="background-color: {{party color|Democratic Party (Japan, 1947)}}" |
! style="font-weight:normal"|[[Hitoshi Ashida|Ashida]] <small>{{nowrap|1948}}</small>
|-
| style="background-color: {{party color|Democratic Liberal Party (Japan)}}" |
! style="font-weight:normal"|[[Shigeru Yoshida|Yoshida]] <small>{{nowrap|1948–54}}</small>
|-
|colspan="9" bgcolor="lightblue"|'''Chair of the Social Democratic Party of Japan, [[Right Socialist Party of Japan|Right]] (1951–1955)'''
|-
|rowspan=2|— || rowspan=2|[[File:Kawakami Jotaro 1952.JPG|100px]]  || rowspan=2|[[Jōtarō Kawakami]]<br /><small>{{nowrap|(1889–1965)}}</small> || rowspan=2|Rep for<br />[[Hyogo 1st district (1947–1993)|Hyogo 1st]] || rowspan=2|19 January 1951 || rowspan=2|12 October 1955 || rowspan=2|—
| style="background-color: {{party color|Liberal Party (Japan, 1950)}}" |
! style="font-weight:normal"|[[Shigeru Yoshida|Yoshida]] <small>{{nowrap|1948–54}}</small>
|-
| style="background-color: {{party color|Japan Democratic Party (1954)}}" |
! style="font-weight:normal"|[[Ichirō Hatoyama|Hatoyama I.]] <small>{{nowrap|1954–56}}</small>
|-
|colspan="9" bgcolor="lightblue"|'''Chair of the Japanese Socialist Party, [[Left Socialist Party of Japan|Left]] (1951–1955)'''
|-
|rowspan=2|— || rowspan=2|[[File:Suzuki Mosaburo.JPG|100px]] || rowspan=2|[[Suzuki Mosaburō]]<br /><small>{{nowrap|(1893–1970)}}</small> || rowspan=2|Rep　for<br />Tokyo 3rd || rowspan=2|18 January 1951 || rowspan=2|12 October 1955 || rowspan=2|—
| style="background-color: {{party color|Liberal Party (Japan, 1950)}}" |
! style="font-weight:normal"|[[Shigeru Yoshida|Yoshida]] <small>{{nowrap|1948–54}}</small>
|-
| style="background-color: {{party color|Japan Democratic Party (1954)}}" |
! style="font-weight:normal"|[[Ichirō Hatoyama|Hatoyama I.]] <small>{{nowrap|1954–56}}</small>
|-
|colspan="9" bgcolor="lightblue"|'''Chair of the Social Democratic Party of Japan, Unified (1955–1996)'''
|-
|rowspan=4|2 || rowspan=4|[[File:Suzuki Mosaburo.JPG|100px]] || rowspan=4|[[Suzuki Mosaburō]]<br /><small>{{nowrap|(1893–1970)}}</small> || rowspan=4|Rep for<br />Tokyo 3rd || rowspan=4|12 October 1955 || rowspan=4|23 March 1960 || rowspan=4|—
| style="background-color: {{party color|Japan Democratic Party (1954)}}" |
! rowspan="2" style="font-weight:normal"|[[Ichirō Hatoyama|Hatoyama I.]] <small>{{nowrap|1954–56}}</small>
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
! style="font-weight:normal"|[[Tanzan Ishibashi|Ishibashi]] <small>{{nowrap|1956–57}}</small>
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-bottom:solid 0 gray" |
! rowspan="2" style="font-weight:normal"|[[Nobusuke Kishi|Kishi]] <small>{{nowrap|1957–60}}</small>
|-
|rowspan=2|3 || rowspan=2|[[File:Inejiro-Asanuma-1.png|100px]] || rowspan=2|[[Inejiro Asanuma]]<br /><small>{{nowrap|(1898–1960)}}</small> || rowspan=2|Rep for<br />[[Tokyo 1st district (1947–93)|Tokyo 1st]] || rowspan=2|23 March 1960 || rowspan=2|12 October 1960<br />(assassinated) || rowspan=2 align=left| {{smalldiv|{{hidden|1960|Inejirō Asanuma – 228<br />Jōtarō Kawakami – 206}}}}
| height=50 style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray" |
|-
| height=50 style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray; border-bottom:solid 0 gray" |
! rowspan="3" style="font-weight:normal"|[[Hayato Ikeda|Ikeda]] <small>{{nowrap|1960–64}}</small>
|-
|— || [[File:Saburo Eda 1963 Salvaged Crop.jpg|100px]]  || ''[[Saburō Eda]]''<br /><small>''{{nowrap|(1907–1977)}}''</small><br />(''acting'') || ''Cou for<br />Okayama at-large'' || ''12 October 1960'' || ''6 March 1961'' || —
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-bottom:solid 0 gray; border-top:solid 0 gray" |
|-
|rowspan=2|4 || rowspan=2|[[File:Jotaro Kawakami Salvaged.jpg|100px]]  || rowspan=2|[[Jōtarō Kawakami]]<br /><small>{{nowrap|(1889–1965)}}</small> || rowspan=2|Rep for<br />[[Hyogo 1st district (1947–1993)|Hyogo 1st]] || rowspan=2|6 March 1961 || rowspan=2|6 May 1965 || rowspan=2|—
| height=50 style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray" |
|-
| height=50 style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray; border-bottom:solid 0 gray" |
! rowspan="4" style="font-weight:normal"|[[Eisaku Satō|Satō]] <small>{{nowrap|1964–72}}</small>
|-
|5 || [[File:Kozo Sasaki 1965 Salvaged Crop.png|100px]] || [[Kouzou Sasaki]]<br /><small>{{nowrap|(1900–1985)}}</small> || Rep for<br />Miyagi 1st || 6 May 1965 || 19 August 1967 || align=left| {{smalldiv|{{hidden|January 1966|Kozo Sasaki – 295<br />Saburō Eda – 276}}}}
{{smalldiv|{{hidden|December 1966|Kozo Sasaki – 313<br />Saburō Eda – 274}}}}
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-bottom:solid 0 gray; border-top:solid 0 gray" |
|-
|6 || [[File:Seiichi Katsumata 1953.png|100px]] || [[Seiichi Katsumata]]<br /><small>{{nowrap|(1908–1989)}}</small> || Rep for<br />Shizuoka 2nd || 19 August 1967 || 4 October 1968 || — 
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-bottom:solid 0 gray; border-top:solid 0 gray" |
|-
|rowspan=4|7 || rowspan=4|[[File:Tomomi-Narita-1.png|100px]]|| rowspan="4" |[[Tomomi Narita]]<br /><small>{{nowrap|(1912–1979)}}</small> || rowspan=4|Rep for<br />Kagawa 1st || rowspan=4|30 November 1968 || rowspan=4|26 September 1977 || rowspan=4 align=left| {{smalldiv|{{hidden|1970|Tomomi Narita – 207<br />Saburō Eda – 148}}}}
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-bottom:solid 0 gray; border-top:solid 0 gray" |
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
! style="font-weight:normal"|[[Kakuei Tanaka|Tanaka K.]] <small>{{nowrap|1972–74}}</small>
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
! style="font-weight:normal"|[[Takeo Miki|Miki]] <small>{{nowrap|1974–76}}</small>
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-bottom:solid 0 gray" |
! rowspan="2" style="font-weight:normal"|[[Takeo Fukuda|Fukuda T.]] <small>{{nowrap|1976–78}}</small>
|-
|rowspan=5|8 || rowspan=5|[[File:Ichio Asukata Crop.png|100px]] || rowspan=5|[[Ichio Asukata]]<br /><small>{{nowrap|(1915–1990)}}</small> || rowspan=5|Rep for<br />Tokyo 1st || rowspan=5|13 December 1977 || rowspan=5|7 September 1983 || rowspan=5 align=left| {{smalldiv|{{hidden|1981|Ichio Asukata – 39379<br />Sanji Mutō – 14721<br />Shōichi Shimodaira – 3425}}}}
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray" |
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
! style="font-weight:normal"|[[Masayoshi Ōhira|Ōhira]] <small>{{nowrap|1978–80}}</small>
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
! style="font-weight:normal"|[[Masayoshi Ito|Ito]] <small>{{nowrap|1980}} (Acting)</small>
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
! style="font-weight:normal"|[[Zenkō Suzuki|Suzuki Z.]] <small>{{nowrap|1980–82}}</small>
|-
| height=50 style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray; border-bottom:solid 0 gray" |
! rowspan="3" style="font-weight:normal"|[[Yasuhiro Nakasone|Nakasone]] <small>{{nowrap|1982–87}}</small>
|-
|9 || [[File:Masashi_Ishibashi.jpg|100px]] || [[Masashi Ishibashi]]<br /><small>{{nowrap|(1924–2019)}}</small> || Rep for<br />Nagasaki 2nd || 7 September 1983 || 8 September 1986 || —
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-bottom:solid 0 gray; border-top:solid 0 gray" |
|-
|rowspan=4|10 || rowspan=4|[[File:Takako Doi in Tokyo congressist election 2.jpg|100px]] || rowspan=4|[[Takako Doi]]<br /><small>{{nowrap|(1928–2014)}}</small> || rowspan=4|Rep for<br />Hyogo 2nd || rowspan=4|9 September 1986 || rowspan=4|31 July 1991 || rowspan=4 align=left| {{smalldiv|{{hidden|1986|Takako Doi – 58670<br />Tetsu Ueda – 11748}}}}
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-bottom:solid 0 gray; border-top:solid 0 gray" |
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
! style="font-weight:normal"|[[Noboru Takeshita|Takeshita]] <small>{{nowrap|1987–89}}</small>
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
! style="font-weight:normal"|[[Sōsuke Uno|Uno]] <small>{{nowrap|1989}}</small>
|-
| height=50 style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray; border-bottom:solid 0 gray" |
! rowspan="2" style="font-weight:normal"|[[Toshiki Kaifu|Kaifu]] <small>{{nowrap|1989–91}}</small>
|-
| rowspan=2|11 || rowspan=2|[[File:Japanese_Socialist_Party_logo.svg|100x100px]] || rowspan=2|[[Makoto Tanabe]]<br /><small>{{nowrap|(1922–2015)}}</small> || rowspan=2|Rep for<br />Gunma 1st || rowspan=2|31 July 1991 || rowspan=2|19 January 1993 || rowspan=2 align=left| {{smalldiv|{{hidden|1991|Makoto Tanabe – 46363<br />Tetsu Ueda – 36358}}}}
| height=50 style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray" |
|-
| height=50 style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray; border-bottom:solid 0 gray" |
! rowspan="2" style="font-weight:normal"|[[Kiichi Miyazawa|Miyazawa]] <small>{{nowrap|1991–93}}</small>
|-
|rowspan=2|12 || rowspan=2|[[File:Sadao Yamahana Morihiro Hosokawa Cabinet 19930809-2.jpg|100px]] || rowspan=2|[[Sadao Yamahana]]<br /><small>{{nowrap|(1936–1999)}}</small> || rowspan=2|Rep for<br />Tokyo 11th || rowspan=2|19 January 1993 || rowspan=2|25 September 1993 || rowspan=2|—
| height=50 style="background-color: {{party color|Liberal Democratic Party (Japan)}}; border-top:solid 0 gray" |
|-
| height=50 style="background-color: {{party color|Japan New Party}}; border-top:solid 0 gray; border-bottom:solid 0 gray" |
| rowspan="2" style="font-weight:normal"|[[Morihiro Hosokawa|Hosokawa]] <small>{{nowrap|1993–94}}</small><br />(''coalition'')
|-
|rowspan=4|13 || rowspan=4|[[File:Tomiichi Murayama 19940630.jpg|100px]] || rowspan=4|[[Tomiichi Murayama]]<br /><small>{{nowrap|(b. 1924)}}</small><br />[[File:Emblem of the Prime Minister of Japan.svg|25px]] || rowspan=4|Rep for<br />Ōita 1st || rowspan=4|25 September 1993 || rowspan=4|19 January 1996 || rowspan=4 align=left|{{smalldiv|{{hidden|1993|Tomiichi Murayama – 65446<br />Masatoshi Ito – 18075}}}}
{{smalldiv|{{hidden|1996|Tomiichi Murayama – 57591<br />[[Tadatoshi Akiba]] – 10440}}}}
| height=50 style="background-color: {{party color|Japan New Party}}; border-top:solid 0 gray" |
|-
| style="background-color: {{party color|Japan Renewal Party}}" |
! style="font-weight:normal"|[[Tsutomu Hata|Hata]] <small>{{nowrap|1994}}</small>
|-
| style="background-color: {{party color|Japan Socialist Party}}" |
| ''himself'' {{small|1994–96}}
|-
| style="background-color: {{party color|Liberal Democratic Party (Japan)}}" |
| style="font-weight:normal"|[[Ryutaro Hashimoto|Hashimoto]] <small>{{nowrap|1996–98}}</small><br />(''coalition, confidence and supply'')
|-
|bgcolor="lightblue" colspan="9"|'''Successor party: [[Social Democratic Party (Japan)#Leaders|Social Democratic Party]] {{small|(centre-left to left-wing)}}'''
|}

== Election results ==
=== General election results ===
{| class="wikitable sortable"
|-
|+ [[House of Representatives (Japan)|House of Representatives]]
|-
! rowspan=2 | Election
! rowspan=2 | Leader
! colspan=3 | Seats
! rowspan=2 | Position
! colspan=2 | Constituency votes
! rowspan=2 | Status
|-
! No.
! ±
! Share
! Number
! %
|- style="text-align:center;"
![[1946 Japanese general election|1946]]
|[[Tetsu Katayama]]
|{{composition bar|92|468|hex={{party color|Japan Socialist Party}}}}
|bgcolor="lightgrey"|
|19.6%
|3rd
|9,924,930
|17.90%
|{{no2|Opposition}}
|- style="text-align:center;"
! rowspan=2|[[1947 Japanese general election|1947]]
| rowspan=2|[[Tetsu Katayama]]
| rowspan=2|{{composition bar|143|466|hex={{party color|Japan Socialist Party}}}}
| rowspan=2|{{increase}} 51
| rowspan=2|30.7%
| rowspan=2|{{increase}} 1st
| rowspan=2|7,176,882
| rowspan=2|26.23%
|{{yes2|JSP-[[Democratic Party (Japan, 1947)|DP]]-[[National Cooperative Party|NCP]] coalition<br />(until 1948)}}
|- style="text-align:center;"
|{{no2|Opposition<br />(since 1948)}}
|- style="text-align:center;"
![[1949 Japanese general election|1949]]
|[[Tetsu Katayama]]
|{{composition bar|48|466|hex={{party color|Japan Socialist Party}}}}
|{{decrease}} 95
|10.3%
|{{decrease}} 3rd
|4,129,794
|13.50%
|{{no2|Opposition}} 
|- style="text-align:center;"
![[1952 Japanese general election|1952]]
|[[Jōtarō Kawakami]]<br />[[Mosaburō Suzuki]]
|{{composition bar|111|466|hex={{party color|Japan Socialist Party}}}}
|{{increase}} 63
|23.8%
|{{increase}} 2nd
|7,507,842
|21.24%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1953 Japanese general election|1953]]
|[[Jōtarō Kawakami]]<br />[[Mosaburō Suzuki]]
|{{composition bar|138|466|hex={{party color|Japan Socialist Party}}}}
|{{increase}} 27
|29.6%
|{{steady}} 2nd
|9,194,547
|26.57%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1955 Japanese general election|1955]]
|[[Jōtarō Kawakami]]<br />[[Mosaburō Suzuki]]
|{{composition bar|156|467|hex={{party color|Japan Socialist Party}}}}
|{{increase}} 18
|33.4%
|{{steady}} 2nd
|10,812,905
|29.21%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1958 Japanese general election|1958]]
|[[Mosaburō Suzuki]]
|{{composition bar|166|467|hex={{party color|Japan Socialist Party}}}}
|{{increase}} 10
|35.5%
|{{steady}} 2nd
|13,093,993
|32.94%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1960 Japanese general election|1960]]
|[[Saburō Eda]]
|{{composition bar|145|467|hex={{party color|Japan Socialist Party}}}}
|{{decrease}} 21
|31.0%
|{{steady}} 2nd
|10,887,134
|27.56%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1963 Japanese general election|1963]]
|[[Jōtarō Kawakami]]
|{{composition bar|144|467|hex={{party color|Japan Socialist Party}}}}
|{{decrease}} 1
|30.8%
|{{steady}} 2nd
|11,906,766
|29.03%
|{{no2|Opposition}}
|- style="text-align:center;" 
![[1967 Japanese general election|1967]]
|[[Kōzō Sasaki]]
|{{composition bar|140|486|hex={{party color|Japan Socialist Party}}}}
|{{decrease}} 4
|28.8%
|{{steady}} 2nd
|12,826,104
|27.88%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1969 Japanese general election|1969]]
|[[Tomomi Narita]]
|{{composition bar|90|486|hex={{party color|Japan Socialist Party}}}}
|{{decrease}} 50
|18.5%
|{{steady}} 2nd
|10,074,101 
|21.44%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1972 Japanese general election|1972]]
|[[Tomomi Narita]]
|{{composition bar|118|491|hex={{party color|Japan Socialist Party}}}}
|{{increase}} 28
|24.0%
|{{steady}} 2nd
|11,478,142
|21.90%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1976 Japanese general election|1976]]
|[[Tomomi Narita]]
|{{composition bar|123|511|hex={{party color|Japan Socialist Party}}}}
|{{increase}} 5
|24.1%
|{{steady}} 2nd
|11,713,009
|20.69%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1979 Japanese general election|1979]]
|[[Ichio Asukata]]
|{{composition bar|107|511|hex={{party color|Japan Socialist Party}}}}
|{{decrease}} 16
|20.9%
|{{steady}} 2nd
|10,643,450
|19.71%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1980 Japanese general election|1980]]
|[[Ichio Asukata]]
|{{composition bar|107|511|hex={{party color|Japan Socialist Party}}}}
|{{steady}} 0
|20.9%
|{{steady}} 2nd
|11,400,748
|19.31%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1983 Japanese general election|1983]]
|[[Masashi Ishibashi]]
|{{composition bar|112|511|hex={{party color|Japan Socialist Party}}}}
|{{increase}} 5
|21.9%
|{{steady}} 2nd
|11,065,083
|19.49%
|{{no2|Opposition}}
|- style="text-align:center;" 
![[1986 Japanese general election|1986]]
|[[Masashi Ishibashi]]
|{{composition bar|85|512|hex={{party color|Japan Socialist Party}}}}
|{{decrease}} 27
|16.6%
|{{steady}} 2nd
|10,412,584
|17.23%
|{{no2|Opposition}}
|- style="text-align:center;"
![[1990 Japanese general election|1990]]
|[[Takako Doi]]
|{{composition bar|136|512|hex={{party color|Japan Socialist Party}}}}
|{{increase}} 51
|26.6%
|{{steady}} 2nd
|16,025,472
|24.39%
|{{no2|Opposition}}
|- style="text-align:center;"
!rowspan=2|[[1993 Japanese general election|1993]]
|rowspan=2|[[Sadao Yamahana]]
|rowspan=2|{{composition bar|70|511|hex={{party color|Japan Socialist Party}}}}
|rowspan=2|{{decrease}} 66
|rowspan=2|13.7%
|rowspan=2|{{steady}} 2nd
|rowspan=2|9,687,589
|rowspan=2|15.43%
|{{yes2|JSP-[[Komeito]]-[[Japan Renewal Party|JRP]]-[[Japan New Party|JNP]]-[[Democratic Socialist Party (Japan)|DSP]]-[[New Party Sakigake|NPS]]-DRP-[[Socialist Democratic Federation (Japan)|SDF]] coalition<br />(until 1994)}}
|-style="text-align:center;"
|{{yes2|[[Liberal Democratic Party (Japan)|LDP]]–JSP–[[New Party Sakigake|NPS]] coalition<br />(until 1996)}}
|}

=== Councillors election results ===
{|class="wikitable"
|-
!Election
!Leader
!No. of<br />seats total
!No. of<br />seats won
!No. of<br />national votes
!% of<br />national vote
!No. of<br />prefectural votes
!% of<br />prefectural vote
|-
|colspan=9 style="text-align:center;" |'''Japanese Socialist Party era'''
|-style="text-align:center;"
![[1947 Japanese House of Councillors election|1947]]
|[[Tetsu Katayama]]
|{{composition bar|47|250|hex={{party color|Japan Socialist Party}}}}
|
|3,479,814
|16.4%
|4,901,341
|23.0%
|-style="text-align:center;"
![[1950 Japanese House of Councillors election|1950]]
|[[Tetsu Katayama]]
|{{composition bar|61|250|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|36|125|hex={{party color|Japan Socialist Party}}}}
|4,854,629
|17.3%
|7,316,808
|25.2%
|-style="text-align:center;"
![[1953 Japanese House of Councillors election|1953]]
|[[Mosaburō Suzuki]]
|{{composition bar|66|250|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|28|125|hex={{party color|Japan Socialist Party}}}}
|5,559,875
|20.7%
|6,870,640
|24.5%
|-style="text-align:center;"
![[1956 Japanese House of Councillors election|1956]]
|[[Mosaburō Suzuki]]
|{{composition bar|80|250|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|49|127|hex={{party color|Japan Socialist Party}}}}
|8,549,940 
|29.9%
|11,156,060
|37.6%
|-style="text-align:center;"
![[1959 Japanese House of Councillors election|1959]]
|[[Mosaburō Suzuki]]
|{{composition bar|85|250|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|38|127|hex={{party color|Japan Socialist Party}}}}
|7,794,754
|26.5%
|10,265,394
|34.1%
|-style="text-align:center;"
![[1962 Japanese House of Councillors election|1962]]
|Jōtarō Kawakami
|{{composition bar|66|250|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|37|127|hex={{party color|Japan Socialist Party}}}}
|8,666,910
|24.2%
|11,917,675
|32.8%
|-style="text-align:center;"
![[1965 Japanese House of Councillors election|1965]]
|[[Kōzō Sasaki]]
|{{composition bar|73|251|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|36|127|hex={{party color|Japan Socialist Party}}}}
|8,729,655
|23.4%
|12,346,650
|32.8%
|-style="text-align:center;"
![[1968 Japanese House of Councillors election|1968]]
|Tomomi Narita
|{{composition bar|65|250|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|28|126|hex={{party color|Japan Socialist Party}}}}
|8,542,199
|19.8%
|12,617,680
|29.2%
|-style="text-align:center;"
![[1971 Japanese House of Councillors election|1971]]
|Tomomi Narita
|{{composition bar|66|249|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|39|125|hex={{party color|Japan Socialist Party}}}}
|8,494,264
|21.3%
|12,597,644
|31.2%
|-style="text-align:center;"
![[1974 Japanese House of Councillors election|1974]]
|Tomomi Narita
|{{composition bar|62|250|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|28|130|hex={{party color|Japan Socialist Party}}}}
|7,990,457
|15.2%
|13,907,865
|26.0%
|-style="text-align:center;"
![[1977 Japanese House of Councillors election|1977]]
|[[Ichio Asukata]]
|{{composition bar|56|249|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|27|126|hex={{party color|Japan Socialist Party}}}}
|8,805,617
|17.3%
|13,403,216
|
|-style="text-align:center;"
![[1980 Japanese House of Councillors election|1980]]
|[[Ichio Asukata]]
|{{composition bar|47|250|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|22|126|hex={{party color|Japan Socialist Party}}}}
|7,341,828
|13.1%
|12,715,880
|
|-style="text-align:center;"
![[1983 Japanese House of Councillors election|1983]]
|[[Ichio Asukata]]
|{{composition bar|44|252|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|22|126|hex={{party color|Japan Socialist Party}}}}
|7,590,331
|16.3%
|11,217,515
|
|-style="text-align:center;"
![[1986 Japanese House of Councillors election|1986]]
|[[Takako Doi]]
|{{composition bar|41|252|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|20|126|hex={{party color|Japan Socialist Party}}}}
|9,869,088
|
|12,464,579
|
|-style="text-align:center;"
![[1989 Japanese House of Councillors election|1989]]
|[[Takako Doi]]
|{{composition bar|68|252|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|45|126|hex={{party color|Japan Socialist Party}}}}
|19,688,252
|35.1%
|15,009,451
|26.4%
|-style="text-align:center;"
![[1992 Japanese House of Councillors election|1992]]
|[[Takako Doi]]
|{{composition bar|71|252|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|22|126|hex={{party color|Japan Socialist Party}}}}
|7,981,726
|17.8%
|7,147,140
|15.8%
|-style="text-align:center;"
![[1995 Japanese House of Councillors election|1995]]
|[[Tomiichi Murayama]]
|{{composition bar|37|252|hex={{party color|Japan Socialist Party}}}}
|{{composition bar|16|126|hex={{party color|Japan Socialist Party}}}}
|6,882,919
|16.9%
|4,926,003
|11.9%
|}

== See also ==
* [[List of political parties in Japan]]

==References==
{{Reflist}}

===Bibliography===
{{refbegin}}
* {{cite book |last = Kapur |first = Nick |year = 2018 |title = Japan at the Crossroads: Conflict and Compromise after Anpo |publisher = Harvard University Press |location = Cambridge, MA |isbn = 978-0674984424 |url = https://books.google.com/books?id=Re5hDwAAQBAJ}}
* {{cite book|last=Mosk|first=Carl|title=Japanese Economic Development: Markets, Norms, Structures|publisher=Routledge|date=2007|isbn=9781135982898}}
{{refend}}

==Works cited==
*{{cite book|last1=Cole |first=Allan |last2=Totten |first2=George |last3=Uyehara |first3=Cecil |title=Socialist Parties In Postwar Japan |publisher=[[Yale University Press]] |year=1966}}

{{Social Democratic Party (Japan)}}
{{authority control}}

[[Category:Japan Socialist Party| ]]
[[Category:1945 establishments in Japan]]
[[Category:1996 disestablishments in Japan]]
[[Category:Christianity in Japan]]
[[Category:Defunct political parties in Japan]]
[[Category:Defunct social democratic parties]]
[[Category:Defunct socialist parties in Asia]]
[[Category:Democratic socialist parties in Asia]]
[[Category:Former member parties of the Socialist International]]
[[Category:Left-wing parties in Japan]]
[[Category:Pacifism in Japan]]
[[Category:Pacifist parties]]
[[Category:Political parties disestablished in 1996]]
[[Category:Political parties established in 1945]]
[[Category:Progressive parties in Japan]]
[[Category:Radical parties]]
[[Category:Social democratic parties in Japan]]
[[Category:Socialism in Japan]]
[[Category:Socialist parties in Japan]]