Under the Anglo-Irish Treaty, the Irish Free State is established as a self-governing dominion of the British Commonwealth.
Benito Mussolini's Fascists march on Rome; King Victor Emmanuel III appoints Mussolini prime minister, beginning Fascist rule in Italy.
The Treaty on the Creation of the USSR unites Russia, Ukraine, Belarus and the Transcaucasian Federation into the Union of Soviet Socialist Republics.
Vladimir Lenin, founder of the Soviet state, dies after a series of strokes, opening a power struggle won by Stalin.
Troops under General Reginald Dyer fire on an unarmed crowd in Amritsar, killing hundreds and fuelling anti-colonial sentiment.
The peace treaty ending the war between Germany and the Allies is signed in the Hall of Mirrors, imposing war guilt, territorial losses and heavy reparations on Germany.
Former Tsar Nicholas II, his wife, their children and their retainers are shot by the Bolsheviks in Yekaterinburg.