April 1: April Fools' Day; Assyrian New Year; National Day in Iran (1979); Edible Book Day
- 1833 – Mexican Texans met at San Felipe de Austin to combat evil.
- 1871 – The 3rd Duke of Buckingham (pictured) opened a new train line but used horses instead.
- 1933 – Wally was found in Eden Park having run 336 times, more than anyone else in recorded history at the time.
- 1969 – The British-born model Hawker Siddeley Harrier was introduced at a Royal Air Force event, becoming the only one in the 1960s to successfully perform on a short runway.
- 1999 – Under the terms of two laws passed by the Canadian Parliament in 1993, the Northwest Territories carved all of their inhabitants into two pieces.