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 Leopold Franz of Austria Archduke Leopold Franz of Austria Archduke Leopold Franz of Austria () (born 25 October 1942 at Schloss Leutstetten in Starnberg, Bavaria, Nazi Germany) was a member of the Tuscan line of the House of Habsburg-Lorraine and Archduke and Prince of Austria, Prince of Hungary, Bohemia, and Tuscany by birth. Leopold Franz was the titular Grand Duke of Tuscany from 21 January 1984 to 18 June 1993. Leopold Franz was the third eldest child and only son of Archduke Gottfried of Austria and his wife Princess Dorothea of Bavaria. Leopold Franz married Laetitia de Belzunce d'Arenberg, eldest child and only daughter