World War I Timeline By facebooker_712141806 Jun 28, 1914 Franz Ferdinand Assassinated Jul 28, 1914 Austria Declares War on Serbia Aug 1, 1914 Germany Declares War Against Russia Aug 3, 1914 Germany invades Belgium Aug 4, 1914 Britain Declares War on Germany May 7, 1915 The Lusitania was sunk by German U-Boat May 23, 1915 Italy Declares War on Germany Feb 1, 1917 Germany started unrestricted submarine warfare Apr 6, 1917 United States Declares War on Germany Nov 6, 1917 Britain launches massive attack on Western Front Aug 8, 1918 Advance of Allies was successful Nov 11, 1918 Germany signs armistice with Allies ending War Jun 28, 1919 Treaty of Versailles
