All times in UTC ·
Dashed edge = started before, or continues beyond, this day
Events on Thursday 21 April 1927 1
1927Great Mississippi FloodThe most destructive river flood in US historyThe Mississippi River broke through levees across seven states, and the Mounds Landing crevasse gave way on 21 April. Around 70,000 square kilometres were flooded and hundreds of thousands of people were displaced. The disaster pushed many African Americans to move north and led to the Flood Control Act of 1928.