Bosnia and Herzegovina the annexation proclamation on 6 October 1908. Despite international furor and objections to the Austro-Hungarian annexation, Russians and their client state, Serbia, were compelled to accept the Austrian-Hungarian annexation of Bosnia Herzegovina in March 1909. In 1910, Habsburg Emperor Franz Joseph proclaimed the first constitution in Bosnia, which led to relaxation of earlier laws, elections and formation of the Bosnian parliament, and growth of new political life. On 28 June 1914, a Yugoslav nationalist youth named Gavrilo Princip, a member of the secret Serbian-supported movement, Young Bosnia, assassinated the heir to the Austro-Hungarian throne, Archduke Franz Ferdinand, in Sarajevo—an event
History of Russia (1892–1917) was Serbia's territorial rival in the region, and Germany remained the Ottoman Empire's protector. Russia tied itself more closely to Serbia than it had previously. The complex system of alliances and Great Power support was extremely unstable; among the Balkan parties harboring resentments over past defeats, the Serbs maintained particular animosity toward the Austro-Hungarian annexation of Bosnia and Herzegovina. In June 1914, a Serbian terrorist assassinated Archduke Franz Ferdinand, heir to the throne of Austria–Hungary, which then held the Serbian government responsible. Austria–Hungary delivered an ultimatum to Serbia. Serbia submitted to the first 2 of 3 cases of the ultimatum;