He began his career as a secretary to Cardinal Alessandro Farnese, iuniore. He was a canon of Florence Cathedral. In 1539, he became vicar of Marche. He became a datary in 1540. He was also a protonotary apostolic.
On July 13, 1541, he was elected Bishop of Fossombrone. He was despatched as nuncio to Francis I of France to encourage peace negotiations with Charles V, Holy Roman Emperor and promote support for holding an ecumenical council. He traveled in the accompany of Cardinal Farnese, who was papal legate to the Kingdom of France and the Kingdom of Spain.
Pope Paul III made him a cardinal priest in the consistory of December 19, 1544. He received the red hat and the titular church of Sant'Apollinare alle Terme Neroniane-Alessandrine. In 1545, he became Prefect of the Apostolic Signatura. He resigned the government of the Diocese of Fossombrone on March 16, 1547.
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