Henri de Montmorency, 4th Duke of Montmorency (1595 – 30 October 1632) was a French nobleman and military commander. Made Grand admiral in 1612, governor of Languedoc in 1614, and by 1620 was viceroy of New France. Despite defeating a Protestant fleet and seizing islands of Re and Oleron, Cardinal Richelieu kept him from taking advantage of these victories. Henri defeated the Duke of Rohan in Languedoc during 1628-1629. He gained notoriety as a military commander in Piedmont during the War of the Mantuan Succession in 1630. Joining the forces of Gaston, Duke of Orleans (the king's brother), Henri raised an army and was severely wounded at Battle of Castelnaudary. Captured, he was executed on 30 October 1632, by a guillotine-like device.