Treaty of Troyes
Henry IV died in 1413. His son and successor, Henry V of England, aware that Charles VI of France's mental illness had caused instability in France, invaded to assert the Plantagenet claims and won a near total victory over the French at the Battle of Agincourt. In subsequent years Henry recaptured much of Normandy and secured marriage to Catherine of Valois. The resulting Treaty of Troyes stated that Henry's heirs would inherit the throne of France, but conflict continued with the Dauphin.