William Seymour, 2nd Duke of Somerset was the great-grandson of Edward Seymour, 1st Duke of Somerset (c.1500-1552), the uncle of King Edward VI and Lord Protector of England. Seymour made a secret marriage at Greenwich on 22 June 1610 to Arbella Stuart (d.1615), daughter of Charles Stuart, 1st Earl of Lennox and Elizabeth Cavendish. Arbella was thirteen years his senior, and King James I disapproved of the marriage as the union of two potential Tudor pretenders to the throne, who were respectively fourth and sixth in line, could only be seen as a threat to the ruling dynasty. As a result, William was condemned to life
Charles Seymour, 6th Duke of Somerset 1748 and was buried in the Seymour Chapel of Salisbury Cathedral in Wiltshire, where survives the elaborate monument to his ancestor Edward Seymour, 1st Earl of Hertford (1539–1621), son of the 1st Duke of Somerset. Shortly before his death he foresaw that his own line of the Seymour family was about to die out in the male line and that as was said of the 9th Duke of Norfolk (d.1777) "the honours of his family were about to pass away from his own line to settle on that of a distant relative". His son and heir apparent Algernon Seymour, Earl