Deaths on February 23

Adolphus Frederick VI, Grand Duke of Mecklenburg-Strelitz (b. 1882)

Adolphus Frederick VI (17 June 1882 – 23 February 1918) was the last reigning grand duke of Mecklenburg-Strelitz.

3 Mar

World War I
Russia signs the Treaty of Brest-Litovsk, agreeing to withdraw from World War I, and conceding German control of the Baltic States, Belarus and Ukraine. It also conceded Turkish control of Ardahan, Kars and Batumi.
2 May

Chevrolet Motor Company
General Motors acquires the Chevrolet Motor Company of Delaware.
24 Jun

Montreal
First airmail service in Canada from Montreal to Toronto.
4 Jul

Nicholas II of Russia
Bolsheviks kill Tsar Nicholas II of Russia and his family (Julian calendar date).
9 Nov

Wilhelm II, German Emperor
Kaiser Wilhelm II of Germany abdicates after the German Revolution, and Germany is proclaimed a Republic.