Great War By chaserowe37 Jun 28, 1914 Arch Duke assasinated Period: Jun 28, 1914 to Jun 28, 1919 WW1 Jul 28, 1914 Austria-Hungary declares war on Serbia Aug 1, 1914 Germany declares war on Russia May 7, 1915 Lusitania sank Jul 1, 1915 Battle of Somme begins Feb 21, 1916 Battle of Verdun begins Aug 6, 1916 Trench warfare Apr 6, 1917 U.S.A declares war on Germany Nov 7, 1917 Bolsheviks overthrow Russisan government Jun 28, 1919 Treaty of Versailles is signed