But when the young Henry V.came to the throne, with the energy and ambition of youth, the time was ripe for the recovery of the lost possessions in France.
The battle of Agincourt (1415) reopened the war with a great defeat for the French chivalry, which represented the Orleanist party.

The wholesale slaughter of princes, bishops, and knights on this fatal day was clear gain for the traitor Burgundy, the champion of the people! The climax of his villainy was at hand.
Henry V., at Rouen, was openly holding his court as King of France.
John, Duke of Burgundy, accompanied by Queen Isabella, presented himself to the invading king, and formally pledged his support and that of his followers to the cause of the English! The infamous treaty of Troyes was signed, 1420.

It provided that Henry should act as regent to Charles VI.

while he lived; that upon the death of that unhappy being he should be Henry V.of England and Henry II.

of France; and that the two kingdoms should thereafter exist under one crown.