Duke of Somerset years after losing his position as Lord Protector, his titles were forfeited and he was beheaded on 22 January 1552. He was replaced in the minority government of Edward VI by John Dudley, Duke of Northumberland, whose pragmatic style contrasted with Seymour's mixture of idealism and arrogance. In 1644 Charles I granted the earldom of Glamorgan to Edward Somerset (1613–1667). He was a descendant of Charles Somerset, the illegitimate son of Henry Beaufort, 3rd Duke of Somerset. In return for obtaining military help from Ireland he promised Edward the title of Duke of Somerset. Under the Commonwealth Edward was banished
Edward Seymour, 8th Duke of Somerset and wife Elizabeth Somner, daughter of John Somner, of Seend. They had at least five children. In December 1740, his father died and Seymour inherited his manors in Wiltshire and Devon. On 11 September 1744, with the unexpected death of George Seymour, Viscount Beauchamp (1725–1744), the only son of Algernon Seymour, 7th Duke of Somerset, the likelihood emerged of Seymour succeeding his distant cousin as Duke of Somerset and Baron Seymour, as the 7th Duke was then aged sixty, and his wife was past child-bearing age. On 23 November 1750 the Duke died, and Seymour duly succeeded to his titles.