Which English king became heir to the throne of France as a result of the 1420 Treaty of Troyes?

Henry V (9 August 1386 – 31 August 1422) was King of England from 1413 until his death at the age of 36 in 1422. He was the second English monarch who came from the House of Lancaster.

After his father's death in 1413, Henry assumed control of the country and embarked on war with France in the ongoing Hundred Years' War (1337–1453) between the two nations. His military successes culminated in his famous victory at the Battle of Agincourt (1415) and saw him come close to conquering France. After months of negotiation with Charles VI of France, the Treaty of Troyes (1420) recognized Henry V as regent and heir apparent to the French throne, and he was subsequently married to Charles's daughter, Catherine of Valois (1401–37). Following Henry V's sudden and unexpected death in France two years later, he was succeeded by his infant son, who reigned as Henry VI (1422–61, 1470–71).