The Treaty of Saint-Clair-sur-Epte was signed in the autumn of 911 between Charles III of France and Rollo, the leader of the Vikings, to settle the Normans in Neustria and to protect Charles' kingdom from any new invasion by the "northmen". No written records survive concerning the creation of the Duchy of Normandy. In addition, Rollo was to be baptised, marry Gisele, the illegitimate daughter of Charles, and become the vassal of the king. [1].