Thomas Seymour, 1st Baron Seymour of Sudeley, KG, PC was a brother of Jane Seymour, the third wife of King Henry VIII. With his brother, Edward Seymour, 1st Duke of Somerset and Lord Protector of England, he vied for control of their nephew, the young King Edward VI. In 1547, Seymour married Catherine Parr, the widow of Henry VIII. During his marriage to Catherine, Seymour involved the future Queen Elizabeth I, who resided in his household, in flirtatious and possibly sexual behaviour.

Jane Seymour was Queen of England as the third wife of King Henry VIII from their marriage on 30 May 1536 until her death the next year. She became queen following the execution of Henry's second wife, Anne Boleyn, who was accused by King Henry VIII of adultery after failing to produce the male heir he so desperately desired. Jane, however, died of postnatal complications less than two weeks after the birth of her only child, the future King Edward VI. She was the only wife of Henry to receive a queen's funeral; and he was later buried alongside her remains in St George's Chapel, Windsor Castle.