A Fragile Tenure: England & Gascony 1216-1337
Robin Studd shows how Henry III's acceptance after 1259 of vassal status for England's one remaining continental territory of Gascony gave enormous scope for interference by the French crown.
Henry II, Richard I and John were Frenchmen who happened also to become kings of England. Their French territories were their homeland; England merely gave to them their most distinguished title. By the accession of Henry III to the throne in 1216, however, so much of the Angevins' French lands had been lost that the political relationship between their territories north and south of the Channel was already beginning to change.