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
Austria-Este and the present heir is Franz, Duke of Bavaria. However, Francis V had decided to retain the Este name in the Habsburg family, and left most of his huge estate to his young cousin Archduke Franz Ferdinand of Austria, with certain conditions, one of which is that the heir and future heirs use the name of Este. The non-territorial property of the Este family thus fell to the line of Archduke Charles Louis, younger brother to then Emperor Francis Joseph, Austria-Este then becoming a sort of "secundogeniture" title within the Austrian imperial family. Although the first heir, Archduke Franz Ferdinand