World War I T. Tant By MrHostetter Jun 28, 1914 The Archduke Franz Ferdinand assassinated at Sarajevo. The new leader got kill and it made the austro-hungarian mad and it started the war. Jul 28, 1914 Austria declared war on Serbia Austria have the war on sebia. Aug 3, 1914 Germany declares war on France. May 23, 1915 Italy declared war on Germany and Austria Iltaly declared war on germany. Nov 11, 1918 Germany signed an armistice with the Allies the official date of the end of World War One.