Gascony and the Anglo-French collision

Gascony made the English king an exceptionally powerful vassal inside France, while competing dynastic claims heightened Philip VI's suspicion. Edward III was simultaneously a sovereign king in England and a duke expected to acknowledge the French crown for his continental lands. Formal homage might preserve Gascony yet weaken an English monarch's standing at home, as Edward II's example suggested. Philip's insecurity about his Valois succession made the English position appear more threatening than Edward initially intended it to be. Both rulers believed they held the stronger political hand, turning a manageable feudal dispute into open conflict. The war's maritime supply lines and trading regions consequently became strategic prizes.