Franz Joseph I of Austria of his only son and heir, Crown Prince Rudolf, in 1889, and the assassination of his wife, Empress Elisabeth, in 1898. After the Austro-Prussian War, Austria-Hungary turned its attention to the Balkans, which was a hotspot of international tension because of conflicting interests with the Russian Empire. The Bosnian Crisis was a result of Franz Joseph's annexation of Bosnia and Herzegovina in 1908, which had been occupied by his troops since the Congress of Berlin (1878). On 28 June 1914, the assassination of his nephew, Archduke Franz Ferdinand, in Sarajevo resulted in Austria-Hungary's declaration of war against the Kingdom of
History of the Balkans war set the stage for the Balkan crisis of 1914 and thus was a "prelude to the First World War." The monumentally colossal World War I was ignited from a spark in the Balkans, when a Bosnian Serb named Gavrilo Princip assassinated the heir to the Austrian throne, Franz Ferdinand. Princip was a member of a Serbian militant group called the Crna Ruka (Serbian for "Black Hand"). Following the assassination, Austria-Hungary sent Serbia an ultimatum in July 1914 with several provisions largely designed to prevent Serbian compliance. When Serbia only partially fulfilled the terms of the ultimatum, Austria-Hungary declared war