Somerset, Edward Seymour, duke of, 1506?–1552, protector of England. He served on various military and diplomatic missions for Henry VIII and, after the marriage of his sister Jane to the king, was created Viscount Beauchamp (1536) and earl of Hertford (1537). In 1544, as lieutenant general in the north, he invaded Scotland and captured and burned Edinburgh. He took part in the 1545 expedition against Boulogne and became captain general there in 1546. On the death (1547) of Henry VIII Seymour gained custody of the young heir, Edward VI (who was Seymour's nephew) and was named protector of the realm by the council of regency. Shortly thereafter he took the posts of lord treasurer and earl marshal and the title duke of Somerset. He managed to free himself from the restrictions of the council and wielded almost royal authority in effecting major Protestant reforms in the church and in relaxing such measures as the heresy and treason laws. He was ably seconded by Archbishop Thomas Cranmer, and their efforts resulted in the adoption of the first Book of Common Prayer, whose use was required by an Act of Uniformity in 1549. Meanwhile Somerset tried to enforce a marriage treaty arranged by Henry VIII between the young Edward VI and Mary Queen of Scots. He invaded Scotland, crushed his opponents at Pinkie (1547), and completely alienated the Scots when he laid waste to SE Scotland. The fall and execution (1549) of his brother, Baron Seymour of Sudeley, lord high admiral, was a strong blow to the protector's authority and power, and John Dudley, earl of Warwick (later duke of Northumberland) took advantage of this and other misfortunes. Joining Thomas Wriothesley, earl of Southampton, and others, he deprived (1549) Somerset of the protectorate and imprisoned him in the Tower of London. Somerset was released in 1550, but a revival of his influence led Warwick to arrest (1551) him again, whereupon he was convicted (1552) on a charge of felony and beheaded. Somerset was a man of firm beliefs and military ability.
See M. L. Bush, The Government Policy of Protector Somerset (1975).