In May, 1347, Thomas petitioned Pope Clement VI, claiming that he had been married to Joan for more than eight years, and that while he was in Prussia William Montagu, earl of Salisbury, married Joan and unjustly detained her. It appears that Joan did go through a form of marriage with Montagu, possibly under compulsion. The Pope determined that Joan and Thomas's marriage was legal and on November 17, 1349, ordered her to be restored to her lawful husband.