Pierre Louis Jean Casimir de Blacas

Pierre Louis Jean Casimir de Blacas d'Aulps, 1st Count (comte), then 1st Duke (duc) of Blacas, and later also 1st Prince of Blacas (10 January 1771, Avignon, Vaucluse, France – 17 November 1839, Vienna, Austria) was a French antiquarian, nobleman and diplomat during the Bourbon Restoration.

He was baptized at Avignon on 11 January 1771. He was the son of an aristocrat from Provence and took an opposing view of the French Revolution. In 1790, while a sous-lieutenant in the Noailles dragoons from Tarn, he fled across the Var to Nice in the Kingdom of Sardinia. From there, he went to the German frontier town of Coblenz and joined the counter-revolutionary émigré army of Louis XVI's cousin, the Prince of Condé. Later, he went through Italy before entering the service of Russia and fighting the French Republic in Switzerland under Alexander Suvorov.

While in the pay of Austria, he then travelled to Warsaw and rejoined the court-in-exile of the pretender to the throne of France, King Louis XVI's younger brother, the Comte de Provence, who charged him with various missions, including one to Saint Petersburg. Despite the help of Joseph de Maistre, the King of Sardinia's diplomatic envoy to the court of the Russian tsar Alexander I, he was only able to gain small advantages for the future king. However, his willingness to do anything for the exiled prince, quickly gained Blacas the trust and confidence of his royal master. In 1809, Blacas was made the pretender's grandmaster of the wardrobe (grand-maître de la Garde-Robe du Roi). After the death of the Comte d'Avaray in 1811, he became Provence's closest advisor and favorite.

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