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
Archduke Albrecht Franz, Duke of Teschen Archduke Albrecht Franz, Duke of Teschen Albert Franz Josef Karl Friedrich Georg Hubert Maria, Archduke of Austria, Prince Royal of Hungary and Bohemia, Duke of Teschen (In German: "Erzherzog Albrecht Franz Josef Karl Friedrich Georg Hubert Maria von Österreich, Herzog von Teschen") – (24 July 1897 – 23 July 1955) was a member of the House of Habsburg and titular pretender to the Duchy of Teschen. Archduke Albrecht Franz was born in Vienna, Austria-Hungary, only son of Archduke Friedrich, Duke of Teschen (1856–1936, son of Archduke Karl Ferdinand of Austria and Archduchess Elisabeth Franziska of Austria) and his wife, Princess