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
Duke of Somerset Duke's death he was succeeded by his eldest son Edward Seymour (1717–1792). He died unmarried and was succeeded by his brother Webb Seymour (1718–1793) who became the 10th Duke. His son Edward Adolphus Seymour (1775–1855) was a noted mathematician and became the 11th Duke upon his father's death. He changed the family name to St. Maur but Seymour was still very often used. The 11th Duke was succeeded by his eldest son Edward Adolphus Seymour (1804–1885) who was created Earl St. Maur, of Berry Pomeroy in 1863. His eldest son who predeceased him Edward A. F. Seymour (1835–1869) was known