- Jun 1 Rhineland Republic forms in Wiesbaden
- Jun 2 Pulitzer prize awarded to Carl Sandburg (Cornhuskers)
- Jun 3 Supreme Liberty Life Insurance Co (Chicago) - first insurance company organized by African Americans formed
- Jun 4 US Congress passes the Women's Suffrage Bill, the 19th Amendment
- Jun 4 US marines invade Costa Rica
- Jun 6 Assent is given to an Act to amend the Canadian Currency Act, 1910
- Jun 6 Finland declares war on bolsheviks
- Jun 6 The Republic of Prekmurje ends
- Jun 7 Sette giugno: Riot in Malta; four are killed.
- Jun 9 General steel strike in France
- Jun 9 Red Army captures Ufa in Russia
- Jun 11 51st Belmont: Johnny Loftus riding Sir Barton wins by 5 lengths over Sweep On; first Trip Crown winner
- Jun 12 Dutch 2nd Chamber accord for equal Christian-public education
23rd US Men's Open
Jun 12 US Open Men's Golf, Brae Burn CC: Walter Hagen defeats Mike Brady by 1 stroke in an 18-hole playoff to win his second and final US Open
- Jun 14 1st nonstop air crossing of Atlantic (Alcock & Brown) leaves Newfoundland
- Jun 15 1st nonstop Atlantic flight (Alcock & Brown) lands in Ireland
- Jun 17 "Barney Google" cartoon strip, by Billy De Beck, premieres
- Jun 19 Opposed to dismemberment of Turkey by the Allies, Mustafa Kemal declares his Turkish Nationalist Congress, headquartered in Ankara, independent of Constantinople
- Jun 20 150 die at the Teatro Yaguez fire, Mayagüez, Puerto Rico
Signing of the Treaty of Versailles
Jun 20 Philipp Scheidemann resigns as chancellor of the new German Republic, which he helped establish, refusing to sign the Treaty of Versailles
- Jun 20 Treaty of Versailles: Germany ends incorporation of Austria
- Jun 20 US National Championship Women's Tennis, Philadelphia CC: Hazel Hotchkiss Wightman beats Marion Zinderstein 6-1, 6-2 for her 4th US singles title
- Jun 21 Social Democrat Gustav Bauer forms a German government
Scuttling at Scapa Flow
Jun 21 The German Navy, feeling betrayed by the terms of the Versailles Treaty, scuttles most of its ships interned at Great Britain's Scapa Flow Naval base in the Orkney Islands
Universal Negro Improvement Association
Jun 23 Marcus Garvey's Universal Negro Improvement Association (UNIA) incorporates
- Jun 23 Nitti government forms in Italy
- Jun 25 1st advanced monoplane airliner flight (Junkers F13)
- Jun 25 Revolt of Spartacus in Hamburg
- Jun 26 NY Daily News begins publishing
- Jun 28 Boston Red Sox Carl Mays pitches a complete doubleheader against NY Yankees, winning 1st game, 2-0, losing 2nd game, 4-1 (Polo Grounds, NYC)
- Jun 28 Treaty of Versailles is signed in France, ending World War I and establishing the League of Nations
Authors
Civil Rights Activists
Inventors
Kings
Revolutionaries
Scientists