Louis René Édouard de Rohan known as Cardinal de Rohan (25 September 1734 – 16 February 1803), prince de Rohan-Guéméné, was a French bishop of Strasbourg, politician, cardinal of the Roman Catholic Church, and cadet of the Rohan family (which traced its origin to the kings of Brittany). His parents were Hercule Mériadec, Prince of Guéméné and Louise Gabrielle Julie de Rohan. He was born in Paris.
Members of the Rohan family had filled the office of Bishop of Strasbourg since 1704, which made them princes of the Holy Roman Empire and the compeers rather of the German prince-bishops than of the French ecclesiastics. Louis de Rohan was destined for this high office from birth. Soon after taking orders, in 1760, he was nominated coadjutor to his uncle, Louis Constantin de Rohan-Rochefort, who then held the bishopric, and he was also appointed titular bishop of Canopus, Egypt. But he preferred the elegant life and the gaiety of Paris to his clerical duties, and had also an ambition to make a figure in politics. In 1761 he was elected to seat 36 of the Académie française.
Louis de Rohan was a member of the palace cabal opposed to the Austrian alliance. This party was headed by the Duc d'Aiguillon who, in 1771, sent Rohan on a special embassy to find out what was being done in Vienna with regard to the partition of Poland. Rohan arrived at Vienna in January 1772, and made a great spectacle of himself with his lavish entertainments. Empress Maria Theresa was hostile to his intrigues; not only did he attempt to thwart her alliance with France, but as a vicar of the Church, he made little secret of his venal lifestyle.