Portrait of William Seymour, 2nd Duke of Somerset, 1st Marquess of Hertford (1587–1660), full-length, in armour, holding a marshal's baton

Though a moderate Royalist who had opposed the King in the House of Lords in the early years of his reign, Seymour became an important commander in the Royalist army during the Civil War and led numerous decisive battles. He negotiated the surrender of Oxford, Charles I’s head-quarters during the wars between 1644 and 1646, and attended the King during his impeachment. The prototype would appear to be the half-length portrait, signed and dated 1656, in the collection of the Duke of Northumberland at Syon House. While other versions exist, this is the only one that includes the pike-men in the background and it has been suggested that it could have been painted by a member of Walker’s studio shortly after the artist’s death in 1658 (Gibson, op.cit.). The portrait certainly postdates 1660 since, although Seymour was created knight of the Garter in 1650, he was not in fact installed until 1660, and no other portrait shows him wearing the Badge of the Order.