May 21, 2005 (Saturday)
- In visiting Calvin College to give a commencement speech, U.S. President George W. Bush is met with a petition by a third of the college faculty, stating "We believe your administration has launched an unjust and unjustified war in Iraq.", and strongly criticizing his policies. (Fox News)
- The Greek entry "My Number One" by Elena Paparizou wins the 50th Annual Eurovision Song Contest in Kiev, Ukraine. 24 countries of the European Broadcasting Union participate in the final, fifteen other countries having been eliminated in Thursdays' semi-finals. (Radio Free Europe) (Eurovision)
- The Sun, the largest selling British tabloid newspaper, publishes more surreptitiously taken pictures of former dictator Saddam Hussein, while claiming to condemn the leaking of the first photographs. Other pictures also published show the imprisoned Ali Hassan al-Majid ("Chemical Ali") and Huda Salih Mahdi Ammash ("Mrs Anthrax"). President Bush intervenes to support an investigation into the leaking of the photos. (Vancouver Sun) (The Statesman) (Guardian Unlimited)
- The 21st annual National Science Olympiad was held in University of Illinois at Urbana–Champaign.
- Kingda Ka, the tallest and fastest roller coaster in the world, opens at Six Flags Great Adventure in Jackson Township, New Jersey.
- Arsenal won the English FA Cup, in the first final to go to a penalty shootout; Arsenal beat Manchester United 5-4 on spot-kicks after 120 minutes of a goalless draw at the Millennium Stadium in Cardiff.
- Livingston drew 1-1 at home to Dundee to survive in the SPL, on the final game of the season. This result relegated the visiting side.