Henry VI (6 December 1421 – 21 May 1471) was King of England from 1422 to 1461 and again from 1470 to 1471, and claimant to the French throne from 1422 to 1453 under the terms of the Treaty of Troyes. He became king of England at the age of nine months following the death of his father, Henry V, and inherited the French claim upon the death of his maternal grandfather, Charles VI of France.
Henry VI's claim to France was increasingly challenged during the latter stages of the Hundred Years' War, and by 1453 English authority there had collapsed entirely. His reign in England was marked by weak royal authority, factional conflict among the nobility, and a prolonged period of mental incapacity beginning in 1453, which contributed significantly to political instability and the outbreak of the Wars of the Roses.
Henry was born during the Hundred Years' War (1337–1453). He is the only English monarch to have been crowned King of France, following his coronation at Notre-Dame de Paris in 1431 as Henry II. His early reign, when England was ruled by a regency government, saw the pinnacle of English power in France. However, setbacks followed once he assumed full control in 1437.