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
Archduke Peter Ferdinand of Austria Archduke Peter Ferdinand of Austria Archduke "Peter Ferdinand" Salvator Karl Ludwig Maria Joseph Leopold Anton Rupert Pius Pancraz of Austria, Prince of Hungary and Bohemia, Prince of Tuscany) (12 May 1874, Salzburg, Austria-Hungary – 8 November 1948, St. Gilgen, Salzburg, Austria) was an Austro-Hungarian archduke and an army commander in the Austro-Hungarian Army during World War I. He was also the titular Grand Duke of Tuscany from 2 May 1921 to 8 November 1948. Peter Ferdinand was the fourth child and third-eldest son of Ferdinand IV, Grand Duke of Tuscany and his wife Alice of Bourbon-Parma. His two elder brothers