Franz Joseph I of Austria the Empire on 6 October 1908. However a diplomatic crisis erupted, as both the Serbs and the Italians demanded compensation for the annexation, which the Austro-Hungarian government refused to entertain. The incident was not resolved until the revision of the Treaty of Berlin in April 1909, exacerbating tensions between Austria-Hungary and the Serbs. On 28 June 1914 Franz Joseph's nephew and heir Archduke Franz Ferdinand, and his morganatic wife Sophie, Duchess of Hohenberg, were assassinated by Gavrilo Princip, a Yugoslav nationalist of Serbian ethnicity, during a visit to Sarajevo. When he heard the news of the assassination, Franz Joseph said
Archduke Karl Ferdinand of Austria He became a Lieutenant Field Marshal of the Austrian Army. In Vienna, on 18 April 1854, Karl Ferdinand married his first cousin, Archduchess Elisabeth of Austria (1831–1903), the widow of Archduke Ferdinand of Austria-Este, and the daughter of Archduke Joseph of Austria, Palatine of Hungary. They had six children: Archduke Karl Ferdinand of Austria Archduke Karl Ferdinand of Austria (Vienna, 29 July 1818 – Gross Seelowitz (Židlochovice Castle), 20 November 1874) was the second son of Archduke Charles, Duke of Teschen (1771–1847) and Princess Henrietta of Nassau-Weilburg, and the maternal grandfather of King Alfonso XIII of Spain. A son of