- Dec 1 Danish parliament passes an act to grant Iceland independence under Danish crown
- Dec 1 Yugoslavia declares independence with a monarchy proclaimed in Belgrade
Wilson Sails for Versailles
Dec 4 US President Woodrow Wilson sails for Versailles Peace Conference in France
- Dec 5 Oil refinery on Curacao opens
- Dec 9 French troops occupies Mainz
- Dec 10 John Heyder becomes president of baseball's National League for the 2nd time
- Dec 13 US army of occupation crosses Rhine, enters Germany
- Dec 14 David Loyd George's coalition Government wins a clear majority in the UK general election
Il Trittico
Dec 14 Giacomo Puccini's opera "Il Trittico" premieres in NYC
- Dec 14 Sinn Féin candidates win 73 of 105 Irish seats in UK general election, though all will refuse to take seats in Westminster, instead meeting at a Dail Eireann in Dublin
- Dec 15 American Jewish Congress holds its 1st meeting
- Dec 16 German troops evacuate Finland, give over Kiev in the Ukraine to revolutionary forces and pull back from Estonia as Bolshevik forces move in
Dempsey vs. Morris
Dec 16 Jack Dempsey KOs Carl Morris in 14 seconds
"Moon of the Caribees"
Dec 20 Eugene O'Neill's play "Moon of the Caribees" premieres in NYC
- Dec 20 The Allies turn their attention to Bolshevik expansion in the East, landing troops in Crimea and Latvia
- Dec 21 Red Sox trade Dutch Leonard, Ernie Shore & Duffy Lewis to Yankees for Ray Caldwell & Slim Love, Frank Gilhooey, Al Walters & $15,000
- Dec 26 1st day of 1st-class cricket in Aust after WW I (Vic v NSW)
- Dec 26 After spending Christmas with American troops in France, Wilson goes to London for preliminary discussions about the forthcoming peace conference
- Dec 27 The Great Poland Uprising against the Germans begins.
Vezina 1st Assist
Dec 28 Montreal's Georges Vezina becomes the first NHL goalie to record an assist during the Canadiens’ 6-3 win over the Toronto Arenas
Hoover Decides Name
Dec 30 John E. Hoover decides to be called J. Edgar Hoover
- Dec 31 Kid Gleason replaces Pants Rowland as Chicago White Sox manager; reach World Series but lose in the "Black Sox" betting scandal; Gleason not involved
Authors
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Scientists