Count Pierre Marie Xavier Raphaël Antoine Melchior de Polignac was born at the Château de Kerscamp,
Hennebont,
Morbihan, France. He was the fourth son and youngest child of Count Maxence Melchior Édouard Marie Louis de Polignac (1857–1936) and his Mexican-born wife, Susana Mariana Estefanía Francisca de Paula del Corazón de Jesús de la Torre y Mier (1858–1913), whom he wed in Paris in 1881. Mexican politician
Ignacio de la Torre y Mier was Pierre's maternal uncle. Pierre was a member of a
cadet branch of the
House of Polignac, one of France's most renowned ducal families, noble since at least the 12th century, duke in 1780,
peer in 1817. His male-line descendants are still in line of succession for the title of
Duke of Polignac. Pierre was a descendant of
Marie Antoinette's
favourite,
Yolande de Polastron, duchesse de Polignac. A veteran of
World War I, Pierre had fraternized in artistic social circles in France, becoming a good friend of
Marcel Proust and
Jean Cocteau. ==Prince==