Henry VI (6 December 1421 – 21 May 1471) was King of England from 1422 to 1461 and again from 1470 to 1471, and disputed King of France from 1422 to 1453 (end of the Hundred Years' War). The only child of Henry V, he succeeded to the English throne at the age of nine months upon his father's death, and succeeded to the French throne on the death of his maternal grandfather, Charles VI, shortly afterwards.

Henry inherited the long-running Hundred Years' War (1337–1453), in which his uncle Charles VII contested his claim to the French throne. He is the only English monarch to have been also crowned King of France, in 1431. His early reign, when several people were ruling for him, saw the pinnacle of English power in France.

The Siege of Orléans in 1429 announced the beginning of the end for English hopes of conquest. Even with the eventual capture of Joan of Arc by the Burgundians and her execution in 1431, a series of crushing French victories such as those at Patay in 1429, Formigny in 1450 and Castillon in 1453 concluded the war in favour of the Valois dynasty (Royal house of France from 1328 to 1589). England permanently lost most of its continental possessions, with only the Pale of Calais remaining under its control on the continent, until it too was lost in the Siege of Calais in 1558.

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