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 Otto of Austria (1865–1906) to repair their relationship with the Saxon royal family, after both Crown Prince Rudolf and Otto's brother Franz Ferdinand had snubbed the Saxons by rejecting Maria's elder sister Mathilde. Otto and Maria had two sons: Their marriage was unhappy, however, since the Archduke was often unfaithful. He had two children by his mistress, Marie Schleinzer: The mountain lodge on the Rax plateau in Lower Austria, is named after him. Archduke Otto of Austria (1865–1906) Otto Franz Joseph Karl Ludwig Maria, Prince Imperial and Archduke of Austria, Prince Royal of Hungary and Bohemia (21 April 1865 – 1 November 1906) was