Battle of Cer 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 and Danube rivers in order to prevent the Austro-Hungarians from using them during any future invasion. Belgrade was shelled
Austria–Germany relations in this unified Germany. Austria-Hungary then turned its imperial ambitions to the Balkan Peninsula; whereas the German Empire focused on building armaments in a race against the United Kingdom (Britain and Ireland). Nevertheless, both the German Empire and Austria-Hungary forged a military alliance with the Kingdom of Italy, forming the Triple Alliance (1882). In the 1910s, Austria-Hungary's ambition of turning Serbia into its protectorate facilitated the Assassination of Archduke Franz Ferdinand (1914), heir to Austria-Hungary's throne. When Austria-Hungary stirred up excuses for a war (First World War) against Serbia, Germany, claiming the Alliance's terms of passive military defence instead of