- Jan 1 The Belorussian Communist Organisation is founded as a separate party.
- Jan 1 6th Rose Bowl: Harvard beats Oregon 7-6
- Jan 2 Responding to global fear of communism caused by the Russian Revolution, US Attorney General Palmer authorizes raids across the country on unionists and socialists
- Jan 3 Arthur Honegger's "Chant de Nigamon," premieres
- Jan 4 1st Black baseball league, National Negro Baseball League, organizes
- Jan 4 Amsterdam actors decide to strike for retirement benefits
- Jan 7 Five duly elected Socialist assemblymen are denied by the New York State Assembly
- Jan 10 Montreal Canadiens (14) & Tor St Patricks (7) score NHL record 21 goals
- Jan 10 Silver reaches record $1.37 an ounce
- Jan 10 Inauguration of the League of Nations held in Paris
- Jan 11 French passenger ship Afrique sinks near La Rochelle; 553 die
- Jan 12 Annual drafting of baseball players from minor leagues to be done in inverse order of the final standings, agreed to
- Jan 13 NY Times editorial (falsely) reports rockets can never fly
- Jan 16 1st assembly of the League of Nations is held in Paris
- Jan 16 Georgia declares independence
- Jan 16 Zeta Phi Beta Sorority Incorporated is founded at Howard University
- Jan 17 Paul Deschanel elected President of France
- Jan 17 First day Prohibition comes into effect in the US as a result of the 18th amendment
- Jan 19 Alexandre Millerand forms French government
- Jan 20 Dutch 2nd Chamber passes school laws
- Jan 20 The American Civil Liberties Union is founded
- Jan 21 14th Davis Cup: Australasia beats Great Britain in Sydney (4-1)
Event of Interest
Jan 23 Dutch refuse to turn over ex-Emperor Wilhelm II of Germany to allies
Wilhelm II
- Jan 24 12th Australasian Championships: Algernon Kingscote beats Eric Pockley (6-4, 6-0, 6-3)
- Jan 26 Amadeo Modigliani's fiancé Jeanne Hébuterne jumps out of a window a day after the artist's funeral killing herself and her unborn child
- Jan 26 Former Ford Motor Co. executive Henry Leland launches the Lincoln Motor Company which he later sold to his former employer
Event of Interest
Jan 29 Walt Disney starts work as an artist with KC Slide Co for $40 a week
Walt Disney
- Jan 31 1st Ukrainian daily newspaper in US (NYC) begins publication
NHL Record
Jan 31 Joe Malone, Quebec Bulldogs, sets NHL record with 7 goals in a game
Joe Malone
- Jan 31 Phi Beta Sigma Fraternity incorporates at Howard University