In 1566 Châtellerault withdrew to his estates in France, where he made vain attempts to regain his confiscated duchy. In 1569, he returned to Scotland in support of Mary but was imprisoned by Murray who assembled a parliament and had him declared a traitor. Murray was assassinated on 23 January 1570 while Châtellerault was still in prison. Nevertheless, Châtellerault was rumoured to have been an accomplice in the regent's murder. Châtellerault was released from prison on 20 April 1570. In 1573 he gave up his support for Mary and recognised Mary's infant son James as King of Scotland.