 He was named a cardinal on 10 December 1539 by Pope Paul III, who then named him Legate in Parma and Piacenza.In 1548 he renounced the bishopric in favour of his relative Cesare Gambara, who participated in the Council of Trent.Maffeo Gambara (1592) was a reformer, as was the Theatine Paolo Aresio (1620).