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
Russian entry into World War I of Austria of Germany and the Austro-Hungarian Empire. The consensus of scholars includes scant mention of Russia, and briefly mentions Russia's defense of Orthodox Serbia, its pan-Slavic roles, its treaty obligations with France, and its concern for protecting it status as a great power. The Archduke Franz Ferdinand of Austro-Hungary was assassinated by Bosnian Serbs on 28 June 1914 to protest Austrian takeover of a largely Slavic province. Vienna was unable to find evidence that Serbia had sponsored the assassination but a month later issued an ultimatum to Serbia, which it knew would be rejected and thus lead to war.