Bulgaria during World War I 28 June 1914, Gavrilo Princip, a Bosnian-Serb student and member of Young Bosnia, assassinated the heir to the Austro-Hungarian throne, the Archduke Franz Ferdinand of Austria in Sarajevo, Bosnia. This began a period of diplomatic manoeuvring between Austria-Hungary, Germany, Russia, France and Britain called the July Crisis. Wanting to end Serbian interference in Bosnia conclusively, Austria-Hungary delivered the July Ultimatum to Serbia, a series of ten demands that were intentionally meant to be unacceptable in order to precipitate a war with Serbia. When Serbia acceded to only eight of the ten demands levied against it in the ultimatum, Austria-Hungary declared
Archduke Peter Ferdinand of Austria Archduke Peter Ferdinand of Austria Archduke "Peter Ferdinand" Salvator Karl Ludwig Maria Joseph Leopold Anton Rupert Pius Pancraz of Austria, Prince of Hungary and Bohemia, Prince of Tuscany) (12 May 1874, Salzburg, Austria-Hungary – 8 November 1948, St. Gilgen, Salzburg, Austria) was an Austro-Hungarian archduke and an army commander in the Austro-Hungarian Army during World War I. He was also the titular Grand Duke of Tuscany from 2 May 1921 to 8 November 1948. Peter Ferdinand was the fourth child and third-eldest son of Ferdinand IV, Grand Duke of Tuscany and his wife Alice of Bourbon-Parma. His two elder brothers