Background
She was the daughter of Edmund Beaufort, 2nd Duke of Somerset, Knight of the Order of the Garter (1406-1455), by his wife, Lady Eleanor Beauchamp daughter of Richard de Beauchamp, 13th Earl of Warwick by his first wife, Elizabeth de Berkeley, daughter and heiress of Thomas de Berkeley, 5th Baron Berkeley by his wife Margaret de Lisle, 3rd Baroness Lisle. Eleanor Beauchamp was an elder half-sister of Henry de Beauchamp, 1st Duke of Warwick and Anne Neville, 16th Countess of Warwick.