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
Austria–Serbia relations of Serbian revolts during the 1848 Revolutions were not opposed by the Habsburg rulers. Serbian claims were not recognized by Hungary was eventually placated with the Austro-Hungarian Compromise of 1867, further angering Serbian nationalists. One notable flare-up between the two countries was the 1906-1909 economic conflict known as the Pig War which occurred simultaneously with the diplomatic and military crisis over the Austrian annexation of Bosnia. Ultimately, the tensions between the two countries could not withstand the strain of Assassination of Archduke Franz Ferdinand of Austria by Bosnian Serbs in 1914. Following the July Crisis, Austria invaded Serbia to punish