The Mayerling incident is the series of events surrounding the apparent murder–suicide pact of Rudolf, Crown Prince of Austria, and his mistress, baroness Mary Vetsera. They were found dead on 30 January 1889 in an imperial hunting lodge in Mayerling. Rudolf, who was married to Princess Stéphanie of Belgium, was the only son of Emperor Franz Joseph and Empress Elisabeth, and was heir apparent to the throne of Austria-Hungary.
Rudolf's mistress was the daughter of Albin von Vetsera, a diplomat at the Austrian court. Albin had been created a Freiherr (Baron) in 1870. The bodies of the 30-year-old Rudolf and the 17-year-old Mary were discovered in the Imperial hunting lodge at Mayerling in the Vienna Woods, 26.6 kilometres (16.5 mi) southwest of the capital, on the morning of 30 January 1889.
The death of the Crown Prince interrupted the security inherent in the direct line of Habsburg dynastic succession. As Rudolf had no son, the succession passed to Franz Joseph's brother, Archduke Karl Ludwig, and his eldest son, Archduke Franz Ferdinand.
This destabilisation endangered the growing reconciliation between the Austrian and Hungarian factions of the empire. Succeeding developments led to the assassination of Archduke Franz Ferdinand and his wife Sophie by Gavrilo Princip, a Yugoslav nationalist and ethnic Serb, at Sarajevo in June 1914, and the July Crisis that led to the start of the First World War.
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