By August 1526 he was the Duke of Bourbon's ambassador to Charles V's court in Granada and he first visited England in September 1526. In the summer of 1527, following the death of the Duke of Bourbon at the sack of Rome, he entered the service of Charles V, Holy Roman Emperor, working under Nicholas Perrenot, seigneur de Granvelle. He held the positions of councillor and master of requests by July 1527, and at Valladolid on 25 June 1529, he was appointed Charles V's ambassador to England.