- 1788 – A fire in New Orleans leaves most of the town in ruins.
- 1952 – Alan Freed presents the Moondog Coronation Ball, the first rock and roll concert, in Cleveland, Ohio.
- 1970 – The first Earth Day proclamation is issued by Mayor of San Francisco Joseph Alioto.
- 1980 – On the season finale of the soap opera Dallas, the infamous character J.R. Ewing is shot by an unseen assailant, leading to the catchphrase “Who shot J.R.?“