May 21 in the history of the Birmingham District:
- 2011: The 32nd annual Do Dah Day was held.
- 2006: Walters & Bellows and the Tim Boykin Blues Band performed in the Phelan Park Music Series.
- 2003: Ruben Studdard was announced as the winner of American Idol.
- 2001: UAB's Hugh Kaul Human Genetics Building was dedicated on 20th Street South.
- 1951: A major fire destroyed a cluster of 20 duplexes in Fairfield while Birmingham Fire Department trucks stood idly by, awaiting Bull Connor's order permitting them to assist.
- 1921: The 1921 National Balloon Race launched from Birmingham, the first event in the city's semicentennial celebrations.
- 1874: Alabama Press Association convention attendees took a train excursion to Blount Springs, with stops at coal mines along the route.
- 2011: Former baseball player and football coach Jim Pyburn died in Jasper.
- 2009: Jim Davenport's Pizza Palace founder Rex Hollis died.
- 1997: Former Birmingham Black Barons player/manager Lorenzo "Piper" Davis died in Birmingham.