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
Archduke Rainer Ferdinand of Austria nominal Minister-President chairing the liberal cabinet of State Minister Anton von Schmerling. Archduke Rainer Ferdinand of Austria Archduke Rainer Ferdinand Maria Johann Evangelist Franz Ignaz of Austria (11 January 1827 – 27 January 1913), a member of the House of Habsburg-Lorraine and nephew of Emperor Francis II, was an Austrian politician who served as Minister-President of Austria from 1861 to 1865. Born in Milan, the capital of the Austrian Kingdom of Lombardy–Venetia, he was a son of Viceroy Archduke Rainer Joseph of Austria (1783–1853) and his consort Princess Elisabeth of Savoy (1800–1856). Rainer Ferdinand spent most of his youth at