Duke of Rambouillet
The Duchy or Duke of Rambouillet was a French Peerage created in 1711 for Louis Alexandre de Bourbon, Légitimé de France, Count of Toulouse, youngest legitimised son of Louis XIV and Madame de Montespan.
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Wikipedia
The Duchy or Duke of Rambouillet was a French Peerage created in 1711 for Louis Alexandre de Bourbon, Légitimé de France, Count of Toulouse, youngest legitimised son of Louis XIV and Madame de Montespan.