April 1: Palm Sunday in Western Christianity (2007); Independence Day in San Serriffe (1967); April Fools' Day; Assyrian New Year.
- 1318 - The Scottish captured Berwick upon Tweed from the English.
- 1957 - About eight million viewers watched a report on the BBC television programme Panorama about spaghetti trees.
- 1970 - U.S. President Richard Nixon (pictured) signed the Public Health Cigarette Smoking Act *into law, banning cigarette advertisements on television and radio in the United States.
- 1997 - Cartoonists of popularly syndicated comic strips swapped cartoons for the day.
- 2006 - Five British policing agencies merged to form the Serious Organised Crime Agency.