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
Anne Seymour, Duchess of Somerset the peerage as Viscount Beauchamp. In October 1537, after the birth of his royal nephew Edward, he was created Earl of Hertford. In 1547, he became a duke, so Anne became the Duchess of Somerset. Anne had ten children by Edward Seymour: Queen Jane stood godmother to Anne's first child. The ceremony was held at Chester Place; besides the queen, Thomas Cromwell and Mary Tudor also acted as godparents. Anne Seymour was present at the wedding ceremony of Henry VIII and Catherine Parr on 12 July 1543. After Henry VIII's death, her husband acted as king in all but name.