- 1911 - The anarchist Mexican Liberal Party captured Tijuana.
- 1912 - George Woodcock was born.
- 1916 - Ben Reitman was sentenced to 60 days in jail for advocating birth control.
- 1919 - Vera Zasulich (pictured) died.
- 1930 - Gary Snyder was born.
- 1937 - Spanish Revolution: The Barcelona May Days end, leaving approximately 500 dead and 1,000 injured.
- 1945 – German anarcho-syndicalist Fritz Kater was injured by a dud bazooka shell.
- 1985 - The Unabomber's eighth bomb exploded at Boeing, in Auburn, Washington.