Margaret de Beauchamp, dau. of John de Beauchamp, 3rd Lord Beauchamp of Bletsho, m. 1st, Sir Oliver St. John, Knt, and conveyed the Barony of Beauchamp, of Bletsho, into that family. Margaret m. 2nd, John Beaufort, Earl of Somerset, and by him was mother of Margaret, Countess of Richmond, whose son ascended the British throne as King Henry VII. [Sir Bernard Burke, Dormant and Extinct Peerages, Burke's Peerage, Ltd., London, 1883, p. 33, Beauchamp, Baron Beauchamp, of Bletsho]
This lady m. 2ndly, John Beaufort, Duke of Somerset, K.G., by whom she was mother of Lady Margaret Beaufort, who m. Edward Tudor, Earl of Richmond, and had a son, Henry, Earl of Richmond, who ascended the throne as Henry VII. [Sir Bernard Burke, Dormant, Abeyant, Forfeited, and Extinct Peerages, Burke's Peerage, Ltd., London, 1883, p. 46, St. John, Earls of Bolingbroke]
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