Coat of arms of Lady Margaret Beaufort, the daughter and sole heiress of John Beaufort, Duke of Somerset (1404–1444), a legitimised grandson of John of Gaunt, 1st Duke of Lancaster (third surviving son of King Edward III) by his mistress Katherine Swynford. She married Edmund Tudor, 1st Earl of Richmond, by whom she was the mother of King Henry VII, the first Tudor king of England.
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