Battle of Kolubara their respective commands, and the 5th and 6th armies were merged into a single 5th Army of 95,000 men. On 28 June 1914, Bosnian Serb student Gavrilo Princip assassinated Archduke Franz Ferdinand of Austria in Sarajevo. The assassination precipitated the July Crisis, which led Austria-Hungary to issue an ultimatum to Serbia on 23 July on suspicion that the assassination had been planned in Belgrade. The Austro-Hungarian government made the ultimatum intentionally unacceptable to Serbia, and it was indeed rejected. The Austro-Hungarians declared war on Serbia on 28 July and that same day the Serbs destroyed all bridges on the Sava
SMS Kaiser Franz Joseph I during the Xinhai Revolution. In 1913, the cruisers were ordered to rotate duties one final time, with "Kaiserin Elisabeth" going to China, and "Kaiser Franz Joseph I" returning to Austria-Hungary in 1914. The assassination of Archduke Franz Ferdinand on 28 June 1914 in Sarajevo triggered a chain of events which led to the July Crisis and Austria-Hungary's subsequent declaration of war on Serbia on 28 July. Events unfolded rapidly in the ensuing days. On 30 July 1914 Russia declared full mobilization in response to Austria-Hungary's declaration of war on Serbia. Austria-Hungary declared full mobilization the next day. On 1 August