The Dual-Monarchy of England and France

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 English and Burgundians until 1435 as King Henry II of France. He was crowned King of France on 16 December 1431.

In practical terms, King Henry's de jure sovereignty and legitimacy as king of France was only recognised in the English and allied-controlled territories of France which were under the domination of his French regency council, while the Dauphin ruled as King of France in part of the realm south of the Loire.

The Dauphin was crowned as King Charles VII of France at Reims on 17 July 1429, largely through the martial efforts of Joan of Arc, who believed it was her mission to free France from the English and to have the Dauphin Charles crowned at Reims. In 1435, the Duke of Burgundy, released from his obligations to Henry VI by a papal legate, recognised Charles VII as the rightful king of France. The defection of this powerful French noble marked the end of Henry's de facto reign over France. The Dual monarchy came to an end with the final victory of the French at the Battle of Castillon on 17 July 1453, thus bringing the Hundred Years' War to a conclusion. The English were expelled from all of the territories which they had controlled in France, with the sole exception of Calais. Charles VII had thus established himself as the undisputed king of almost all of France.

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