Jane's father was Sir John Seymour of Wolf Hall, Savernake, Wiltshire. She became a lady in waiting to Henry's first wife, Catherine of Aragon, and then to Anne Boleyn, who married the King in 1533. Henry probably became attracted to Jane in 1535, when he visited her father at Wolf Hall, but, though willing to marry him, she refused to be his mistress. That determination undoubtedly helped bring about Anne Boleyn's downfall and execution (May 19, 1536). On May 30, 1536, Henry and Jane were married privately.

During the remaining 17 months of her life Jane managed to restore Mary, Henry's daughter by Catherine of Aragon, to the King's favour. Mary was a Roman Catholic, and some scholars have interpreted Jane's intercession to mean that she had little sympathy with the English Reformation. The future Edward VI was born on Oct. 12, 1537, but, to Henry's genuine sorrow, Jane died 12 days later.

Jane's family enjoyed Henry's favour until the end of his reign. On the accession of Edward VI to the throne, Jane's brother, Edward Seymour, earl of Hertford, became regent as lord protector with the title duke of Somerset. Another brother, Thomas Seymour of Sudeley, was lord high admiral from 1547 to 1549.