World War 1 By tyler.bogan May 2, 1905 Schlieffen Pan developed Jun 28, 1914 Assassination Jul 28, 1914 Start of War Sep 6, 1914 1st Battle of Marne May 7, 1915 Sinking of the Lusitania Feb 21, 1916 Battle of Verdun Jul 1, 1916 Battle of Somme Apr 6, 1917 U.S. enters the war Dec 5, 1917 Russian Revolution Sep 26, 1918 Battle of Argonne Forest and Meuse River Nov 11, 1918 End of War Jun 28, 1919 Versailles Treaty