- May 1 British coal miners go on strike
Hall of Fame
May 1 Baseball Hall of Fame pitcher Satchel Paige (19) debuts in the Negro Southern League for Chattanooga
- May 2 US military intervenes in Nicaragua
Volunteers Help Defeat General Strike
May 3 Britain's Trade Union Congress calls for the country's first ever general strike, begins at 1 minute to midnight in support striking coal miners, lasts 9 days
- May 3 Pulitzer prize awarded to Sinclair Lewis (Arrowsmith)
- May 3 US Marines land in Nicaragua (9 months after leaving), stay until 1933
- May 5 Sinclair Lewis refuses his Pulitzer Prize for "Arrowsmith"
- May 8 A. Philip Randolph organizes Brotherhood of Sleeping Car Porters
- May 8 Fire breaks out in Fenway Park, home of Boston Red Sox baseball team
Historic Event
May 9 1st flight over the North Pole claimed by Richard E. Byrd and co-pilot Floyd Bennett. Later discovery of Byrd's diary suggests they may have turned back 150 miles short of the pole due to an oil leak.
Historic Event
May 12 Airship Norge is the first vessel to fly over North Pole, lead by Roald Amundsen and piloted by Umberto Nobile
Music Premiere
May 12 Dmitri Shostakovich's 1st Symphony premieres in Leningrad
Coup d'état
May 12 General Józef Piłsudski returns to power in Poland after coup d'état against the Witos regime
Historic Event
May 17 Chiang Kai-shek is made supreme warlord in Canton
- May 17 Wilhelm Marx succeeds Hans Luther as Chancellor of Germany
- May 18 Evangelist Aimee Semple McPherson vanishes in Venice, California She shows up a month later saying she's been kidnapped
- May 19 French air force bombs Damascus Syria
- May 20 Belgian government of Jaspar takes power
- May 20 Congress passes Air Commerce Act, licensing of pilots & planes
- May 20 Railway Labor Act became law in USA
Film & TV History
May 20 Thomas Edison says Americans prefer silent movies over talkies
- May 21 White Sox Earl Sheely hits a record 6th consecutive double
- May 22 "Five Foot Two, Eyes of Blue" by Gene Austin hits #1
- May 22 Chiang Kai-shek replaces communists in Guomindang China
- May 22 Dutch Communist Party expels David Wijnkoop
- May 23 Chicago Cub's Hack Wilson is 1st to hit a home run off Wrigley Field scoreboard
- May 23 Lebanese constitution forms under French mandate
World Record
May 24 Finnish runner Paavo Nurmi sets world 3000m record (8:25.4) in Berlin, Germany
- May 25 Sholom Schwartzbard assassinates Symon Petliura, the head of the Paris-based government-in-exile of the Ukrainian People's Republic
- May 26 Lebanon adopts constitution
- May 28 Military coup by General Manuel Gomes da Costa in Portugal
- May 28 US Customs Court created by congress
- May 31 Portuguese president Bernardino Machedo resigns after coup
- May 31 Sesquicentennial Exposition opens in Philadelphia
- May 31 Indianapolis 500: First rain-shortened race in "500" history; Frank Lockhart wins after 20 lap duel with Dave Lewis; race called after 400 miles (160 laps)
- May 31 Kruger National Park is established as South Africa's first national park