Polignac, an ancient French family, which claims to derive its name from a castle—the ancient Apolliniacum—in the department of Haute-Loire, and which since the 9th century possessed the district of Velay. Among its most famous members was Cardinal Melchior de Polignac (1661-1742), who was employed in diplomatic missions in Poland and at Rome, and received a cardinal's hat after acting as plenipotentiary of Louis XIV. at the peace of Utrecht (1712). From 1725 till 1732 he was French minister at the court of Rome, and he was appointed Archbishop of Auch. Polignac succeeded Bossuet at the French Academy in 1704, and left unfinished the Anti-Lucretius (1745), a poem intended for a refutation of Lucretius.
Some other members of the Polignac family are more notorious than noteworthy.—In the reign of Louis XVI. Iolanthe-Martine Gabrielle de Polastron, Duchesse de Polignac (born 1749; died at Vienna, 9th December 1793), and her husband, Jules, Duc de Polignac (died at St Petersburg, 1817), grand-nephew of the cardinal, were among the worst, but unhappily most favoured, advisers of Marie Antoinette. They obtained vast sums of the public money from their royal master and mistress, and were largely responsible for the shameful extravagance of the court. The Polignacs knew how they were hated, and were the first of the noblesse to emigrate. From the Empress Catharine of Russia the duke received an estate in the Ukraine, and did not return to France at the Restoration.—His son, AUGUSTE JULES ARMAND MARIE, PRINCE DE POLIGNAC, was born at Versailles, 14th May 1780. On the Restoration he returned to France; became intimate with the Comte d'Artois, afterwards Charles X.; from his devotion to the policy of Rome received from the pope in 1820 the title of Prince; was appointed ambassador at the English court in 1823; and finally, in 1829, became head of the last Bourbon ministry, in which capacity he promulgated the fatal ordonnances that cost Charles X. his throne. He then attempted to flee, but was captured at Granville on the 15th of August, was tried, and condemned to imprisonment for life in the castle of Ham, but was set at liberty by the amnesty of 1836. He took up his residence in England, but died at St Germain, 2d March 1847. He was a puzzle-headed man; 'a mere idiot' Guizot called him to Bishop Wilberforce.—His son, Prince Armand (1817-90), was a leading monarchist.