René II, Viscount of Rohan (1550-1586) the son of René I of Rohan-Gié, a descendant of Francis I, Duke of Brittany and his 2nd wife Isabella Stewart, and of Isabella d'Albret, daughter of John III of Navarre and Catherine of Navarre, Queen-regnant of Navarre.
René II married Catherine of Parthenay and had several children, including Henri II, Duke of Rohan, a renowned soldier and author, and Catherine de Parthenay, from whom are descended (among many others), Prince Philip, consort of Elizabeth II, Queen of Great Britain.