June 6: National holiday of Sweden observed.
- 1523 - Gustav Vasa became King of Sweden, marking the end of the Kalmar Union.
- 1683 - Oxford University's Ashmolean Museum, the world's first university museum, opened.
- 1894 - Colorado Governor Davis H. Waite ordered his state militia to protect and support the miners engaged in the Cripple Creek miners' strike.
- 1933 - The first ever drive-in theater opened in Camden, New Jersey, United States.
- 1944 - The Battle of Normandy began with 155,000 Allied troops landing on the beaches of Normandy in the largest amphibious military operation in history. (pictured)
- 1982 - A war in Lebanon began when Israeli forces invaded southern Lebanon to root out members of the Palestine Liberation Organization.
- 2005 - The U.S. Supreme Court delivered its landmark legal decision in Gonzales v. Raich, allowing the U.S. Congress to ban medical marijuana even in states that approve its use.