Louis François Armand de Vignerot du Plessis, 3rd Duke of Richelieu ([a?m?~d de vi?e?ot du plesis]; 13 March 1696 – 8 August 1788), was a French soldier, diplomat and statesman.
He joined the army and participated in three major wars.
He eventually rose to the rank of Marshal of France.
He was the son of Armand Jean de Vignerot du Plessis, 2nd Duke of Richelieu, who in turn was a great-nephew of Cardinal Richelieu, the prominent French statesman who had dominated France in the early 17th century.