Thomas Seymour was born in Wulfhall, Wiltshire in 1508, the son of John Seymour and the brother of Jane and Edward Seymour. He served as a diplomat under his brother-in-law, King Henry VIII, during the 1530s, being sent to the embassy at the French court in 1538. Seymour also assisted in the delivery of Anne of Cleves and Catherine Parr to the English court to marry the king, and he went on to marry Catherine Parr after the King's death. He also sat on the regency council for the young King Edward VI of England, and he engaged in scandalous behavior with the young Princess Elizabeth, indulging in daily romps with her, tickling her, and slapping her on the behind as she lay in her bed. In 1547, Seymour, jealous of his brother Edward's position as Lord Protector, attempted to wrest power from him as he was absent from court while on campaign against Scotland. As Lord High Admiral, Seymour asked pirates for support in a rebellion against his brother, and he was later caught trying to break into the King's apartments at Hampton Court Palace in 1549. He was charged with high treason, and he was executed on 20 March 1549.