568.
Henry, earl of Richmond, was at this time detained in a kind of honorable custody by the duke of Brittany; and his descent, which seemed to give him some pretensions to the crown, had been a great object of jealousy both in the late and in the present reign.

John, the first duke of Somerset who was grandson of John of Gaunt, by a spurious branch but legitimated by act of parliament, had left only one daughter, Margaret; and his younger brother, Edmund, had succeeded him in his titles, and in a considerable part of his fortune.

Margaret had espoused Edmund, earl of Richmond, half brother of Henry VI., and son of Sir Owen Tudor and Catharine of France, relict of Henry V., and she bore him only one son, who received the name of Henry, and who, after his father's death, inherited the honors and fortune of Richmond.

His mother, being a widow, had espoused in second marriage Sir Henry Stafford, uncle to Buckingham, and after the death of that gentleman, had married Lord Stanley; but had no children by either of these husbands; and her son Henry was thus, in the event of her death, the sole heir of all her fortunes.

But this was not the most considerable advantage which he had reason to expect from her succession: he would represent the elder branch of the house of Somerset; he would inherit all the title of that family to the crown; and though its claim, while any legitimate branch subsisted of the house of Lancaster, had always been much disregarded, the zeal of faction, after the death of Henry VI., and the murder of Prince Edward, immediately conferred a weight and consideration upon it.
Edward IV., finding that all the Lancastrians had turned their attention towards the young earl of Richmond as the object of their hopes, thought him also worthy of his attention; and pursued him into his retreat in Brittany, whither his uncle, the earl of Pembroke, had carried him, after the battle of Tewkesbury, so fatal to his party.