Mathilde l'Emperesse
In 1151 Eustace joined his brother-in-law Louis VII in a raid upon Normandy, also contested between Empress Matilda and King Stephen. This was short-lived, however, when Louis accepted the homage of Henry Plantagenet, son of Empress Matilda, for Normandy. The following year, Eustace was in France as part of a wider coalition of Henry's enemies, but Henry's control of the duchy remained unshaken.