- 570 – Muhammad born
- 1889 – Adolf Hitler born
- 1893 – Joan Miró born
- 1912 – Bram Stoker dies
- 1953 – MKULTRA
- 1970 – Earth Day
- 1979 – President Carter attacked by Rabbit
- 1985 – ATF raid on The Covenant, The Sword, and the Arm of the Lord compound
- 1992 – Benny Hill dies
- 1999 – Columbine High School massacre
April 19
- 1995 – Oklahoma City Bombing
- 1993 – ATF raid on Branch Davidian compound