Prince Leopold Clement Philipp August Maria of Saxe-Coburg and Gotha (19 July 1878 in Szent-Antal, Hungary – 27 April 1916 in Vienna) was an Austro-Hungarian officer and the heir apparent to the wealth of the House of Koháry. His death in a murder-suicide shocked the royal courts of Austria and Germany.

Prince Leopold Clement was the elder child and only son born in the troubled marriage of Princess Louise of Belgium and Prince Philipp of Saxe-Coburg and Gotha, both of whom were Roman Catholic members of the House of Saxe-Coburg and Gotha. He shared his name with his maternal grandfather, King Leopold II of Belgium, and a number of other Coburger relatives. Prince Leopold Clement was the sole heir to the wealth his father's family had inherited from their ancestress, Princess Maria Antonia Koháry de Csábrág.

A Hussar captain in the Austro-Hungarian Army, Prince Leopold Clement met a Viennese girl named Camilla Rybicka at a charity bazaar in 1913. Rybicka was one of the daughters of Court Councillor Rybicka, an officer in the Vienna State Police. Then in her early twenties, she belonged to high society, but was nevertheless a commoner. The two soon started a romantic relationship. Rybicka left the family home, and the two travelled around the Austro-Hungarian Empire before settling down in an apartment in Vienna.

Rybicka, however, was not satisfied with being only the Prince's lover and demanded that he marry her. In Paris on 1 July 1914, Prince Leopold Clement wrote her a letter, promising to marry her within six months, naming her his sole heir, and requesting his father to pay her 2 million Austro-Hungarian krones in the event of his death. After Prince Leopold Clement was called to fight in the First World War, she insisted that he marry her before leaving. Leopold Clement was aware that such a mesalliance would have deprived him of the fortune he stood to inherit because his father had no intention of permitting the union, and that marrying Rybicka would have forced him to resign his officer's commission.

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