- Apr 1 Montreal Maroons' Clint Benedict becomes first NHL goalie to record 3 straight playoff shutouts, in a 3-0 win against the visiting Victoria Cougars in Game 2 of the Stanley Cup Championship series
- Apr 2 Riots between Muslims & Hindus in Calcutta
- Apr 3 Italy establishes corp of force in order to break powerful unions
Liquid-Fueled Rocket
Apr 3 Second flight of a liquid-fueled rocket by Robert Goddard
- Apr 11 Flemish Economic Covenant (VEV) forms in Ghent
The Pleasure Garden
Apr 12 Alfred Hitchcock releases his first film as director "The Pleasure Garden", in England; the silent drama was made in Germany
- Apr 12 Dutch Catholic Radio Broadcast (KRO) forms
Johnson's 7th Shutout
Apr 13 At 38, Walter Johnson pitches his 7th opening day shutout
- Apr 13 Cyclists without bicycle-tax-stamp rounded up in Amsterdam
Lady, Be Good!
Apr 14 George Gershwin and Ira Gershwin's 1st collaborative musical "Lady, Be Good!", featuring siblings Fred Astaire and Adelle Astaire as a brother and sister dance team, opens at Empire Theatre, London's West End; runs for 326 performances
- Apr 15 Sesquicentennial Stadium opens in Philadelphia, Pennsylvania; renamed Philadelphia Municipal Stadium, later renamed JFK Stadium (demolished 1992); played host to Tunney-Demspy fight (1926); 41 Army-Navy football games; professional football; and many concerts, including the US portion of Live-Aid (1985)
- Apr 16 Book of the Month Club sends out its 1st selections "Lolly Willowes" & "Loving Huntsman" by Sylvia Townsend Warner
- Apr 18 Rhein Stadium opens in Dusseldorf, Germany
- Apr 19 30th Boston Marathon won by Canadian Johnny Miles in 2:25:40.4
- Apr 20 1st check sent by radio facsimile transmission across Atlantic
- Apr 22 Persia, Turkey & Afghanistan sign treaties of security
Turandot
Apr 25 Giacomo Puccini's opera "Turandot" premieres in Milan
- Apr 25 Persian cossack officer Reza Chan crowns himself Shah Palawi
- Apr 26 Germany & Russia sign neutrality peace treaty
- Apr 26 Karachai Autonomous Region forms in RSFSR (until 1943)
- Apr 29 France and US reach accord on repayment of WW I