- Mar 1 Germany's prohibition of Communist Party KPD lifted
- Mar 3 German & Turkish friendship/trade treaty signed
- Mar 3 Sean O'Casey's "Juno & the Paycock" premieres in Dublin
- Mar 4 "Happy Birthday To You" published by Claydon Sunny
- Mar 5 Computing-Tabulating-Recording Corp becomes IBM
- Mar 5 Frank Carauna, becomes 1st to bowl 2 successive perfect 300 games
- Mar 5 King Hussein of Hedzjaz appoints himself kalief
- Mar 6 British Labour government cuts military budget
- Mar 8 Coal mine explosion kills 171 at Castle Gate, Utah
- Mar 9 South Slavia aproves Italy's annexation of Fiume (Rijeka)
- Mar 11 3rd term of Belgium Theunis government begins
- Mar 11 Eden Phillpotts' "Farmer's Wife" premieres in London
- Mar 11 NHL Championship: Montreal Canadiens sweeps Ottawa Senators in 2 games
Theater Premiere
Mar 17 Eugene O'Neill's play "Welded" premieres in NYC
- Mar 17 Netherlands & USSR begin talks over USSR recognition
- Mar 17 Sweden & USSR exchange diplomats
Film Release
Mar 18 Silent film classic "The Thief of Bagdad" based on One Thousand and One Nights, starring Douglas Fairbanks and directed by Raoul Walsh is released
Music Premiere
Mar 24 1st performance of Jean Sibelius' 7th Symphony in C at the Konsertföreningenin in Stockholm
- Mar 24 Greece becomes a republic
- Mar 25 Greek parliament selects admiral Paul Koundouriotis as premier
- Mar 25 Stanley Cup Final, Ottawa Auditorium, Ottawa, ON: Montreal Canadiens (NHL) beat Calgary Tigers (WCHL), 3-0 for a 2-0 series sweep
- Mar 26 Premiere of Bernard Shaw's play "Saint Joan" opens in London
- Mar 27 Canada recognizes USSR
- Mar 27 New French government of Poincaré begins
- Mar 28 83rd Grand National: Bob Trudgill wins aboard 25/1 shot Master Robert; last GN from a general riding start, now-familiar 'tape' introduced the following year.
- Mar 28 WGN-AM in Chicago IL begins radio transmissions
- Mar 29 Bavaria & Vatican reach accord
- Mar 31 Croydon Airport, London: Imperial Airways established
- Mar 31 London public transport strike ends