As the result of his conquests, the Cotentin Peninsula was included theoretically in the territory of the Duchy of Brittany, after the Treaty of Compiègne (867) with the king of the Franks.
Ca urmare a cuceririlor sale, Peninsula Cotentin a fost inclusă teoretic în teritoriul Ducatului de Bretania, după Tratatul de la Compiègne (867), încheiat cu regele francilor.