The dual monarchy of England and France existed during the latter phase of the Hundred Years' War when Charles VII of France and Henry VI of England disputed the succession to the throne of France. It commenced on 21 October 1422 upon the death of King Charles VI of France, who had signed the Treaty of Troyes which gave the French crown to his son-in-law Henry V of England and Henry's heirs. It excluded King Charles's son, the Dauphin Charles, who by right of primogeniture was the heir to the Kingdom of France. Although the Treaty was ratified by the Estates-General of France, the act was a contravention of the French law of succession which decreed that the French crown could not be alienated. Henry VI, son of Henry V, became king of both England and France and was recognized only by the