 He studied at the universities of Leuven and Paris.In 1550 his uncle Cristoforo, named Governor of Milan, entrusted him the administration of the Bishopric of Trento, where the Council of Trent had been in intermittent progress since 1545; it was to continue until 1563.After numerous important diplomatic and political experiences (including the mourning discourse at Charles V's funeral), he was created cardinal in 1561 by Pope Pius IV, given the titular church of San Callisto.