Following the assassination of Archduke Franz Ferdinand of Austria by Serb nationalists of the Black Hand secret society on 28 June 1914, Austria delivered the July Ultimatum to Serbia demanding that the Austrian police and military have the right to enter Serbia. Serbia rejected the ultimatum and on 28 July 1914, Austria-Hungary declared war on Serbia. On August 6, the Emperor Franz Joseph signed the Austro-Hungarian declaration of war on Russia, who had since 1 August been at war with Germany, the ally of Austria. Russia and Austria would fight to the point of exhaustion on the bloody Eastern Front. The war ended with the overthrow of monarchy in both countries, as well as in Germany, and the dissolution of their empires.