World War I By marykatheryngibson Jun 28, 1914 Francis Ferdinand assassinated Austria- Hungary's archduke was assassinated while visiting Sarajevo, Bshina. Period: Jun 28, 1914 to Aug 28, 1919 WWI Jul 28, 1914 Austria- Hungary declares war on Serbia Russia mobilizes Aug 4, 1914 Great Britain declares war on germany for violation of Belgium's neutrality May 7, 1915 The Lusitania sunk due to German U-boats Jan 16, 1917 Zimmerman note was sent to Mexico from Germany Apr 6, 1917 U.S joins the war due to continued unrestricted warfare Nov 11, 1918 Armistice was formed Jan 18, 1919 Treaty if Versaillies Period: Jun 28, 1919 to Jun 29, 1919 Article 231
