World War I By Charliec1 Jun 28, 1914 Archduke killed Jun 28, 1914 Austria-Hungary declares war on Serbia 1915 First use of gas as a weapon by the Germans April 1915 May 7, 1915 Sinking of the Lusitania 1916 Wilson reelected; pledged American neutrality 1917 Zimmerman Note 1917 U.S declares war 1917 Bolsheviks led by Lenin overthrow Russian government (November 1917) Nov 11, 1918 . War ends (November 11, 1918) Jun 28, 1919 Treaty of Versailles (June 28, 1919
