 He was a founder of the abbey that became Port-Royal.Eudes de Sully and his brother, Henry, archbishop of Bourges, were sons of Eudes of Sully.The elder Eudes was in turn son of William of Blois, lord of Sully, the elder brother of Theobald II, Count of Champagne, Stephen of England and Henry of Blois, bishop of Winchester and grandson of William the Conqueror.