Rohan, Louis René Édouard, prince de, 1734-1803, French churchman and politician, cardinal of the Roman Catholic Church. Although he succeeded (1779) his uncle as archbishop of Strasbourg, he spent most of his career in Paris. As French ambassador to Vienna (1772) he aroused the dislike of Empress Maria Theresa. In France, his anti-Austrian attitude earned him the hostility of her daughter, the French queen Marie Antoinette. It was apparently in a desire to curry favor with the queen that he became involved in the Affair of the Diamond Necklace. For his inglorious part in this he was acquitted of guilt (1786) but lost his office of grand almoner and was banished from Paris. He was elected to the States-General (1789), refused to sign the Civil Constitution of the Clergy (1791), and emigrated.