WW I Dates By Oliver124 Jun 28, 1914 Assasination of Archduke Ferdinand May 7, 1915 The Lusitania is sunken Mar 24, 1916 Germany promises to warm ships before attacking with the Sussex pledge Jan 31, 1917 Germany ends the Sussex and goes back to undeclared warfare Mar 8, 1917 Revolutions in Russia bring the Bolsheviks back to power Apr 6, 1917 U.S. officially joins the war Mar 3, 1918 Russia's Lenin is able to sign a peace treaty with Germany and that gives Germany a big fighting advantage. Russia leaves the war Nov 11, 1918 Finally the Allies are able to cease fire and end the war. May 7, 1919 The Treaty of Versailles is signed leaving Germany in a pile of debt and embarrasment Jun 19, 1919 The League of Nations was formed