Melchior de Polignac (October 11, 1661 - November 20, 1742), was a French diplomat.

A younger son of Armand XVI, marquis de Polignac, he was born at Puy-en-Velay. At an early age he achieved distinction as a diplomat. In 1695 he was sent as ambassador to Poland, where he succeeded in bringing about the election of François-Louis de Bourbon, prince de Conti as successor to John Sobieski (1697). The subsequent failure of this intrigue led to his temporary disgrace, but in 1702 he was restored to favour, and in 1712 he was sent as the plenipotentiary of Louis XIV of France to the congress of Utrecht.

During the regency he became involved in the "Cellamare plot", and was relegated to Flanders for three years. From 1725 to 1732 he acted for France at the Vatican, in 1726 he received the archbishopric of Auch, and he died at Paris in 1742. He left unfinished a metrical refutation of Lucretius which was published after his death by the abbé de Rothelin (Anti-Lucretius, 1745), and was very popular in its day.

Reference

• This entry incorporates public domain text originally from the 1911 Encyclopaedia Britannica.