Carlo de' Medici (19 March 1595 - 17 June 1666) was an Italian nobleman and Cardinal of the Roman Catholic Church.
Born into the powerful and wealthy Florentine House of Medici, he was the fifth child and third son of Ferdinando I de' Medici, Grand Duke of Tuscany and his wife, Christina of Lorraine. His paternal grandparents were Cosimo I de' Medici, Grand Duke of Tuscany, and his wife, Eleanor of Toledo, the daughter of Pedro Álvarez de Toledo, Marquis of Villafranca, the Spanish viceroy of the Kingdom of Naples. His maternal grandparents were Charles III, Duke of Lorraine and his wife, Claude of Valois, granddaughter of Henry II, King of France and Catherine de' Medici.
Born in Florence, as a younger son into an influential Italian noble family, he was destined for a career in Church. Fulfilling his promise, he had a successful ecclesiastical career, rising to become Cardinal Bishop of Ostia and Dean of the College of Cardinals.De' Medici was raised to the cardinalate by Pope Paul V in the consistory of 2 December 1615 and was made Cardinal Deacon of Santa Maria in Domnica. He was an elector at the papal conclaves of 1621 and 1623 that elected Pope Gregory XV and Pope Urban VIII. He transferred deaconries to that of San Nicola in Carcere in 1623, and was the Cardinal protodeacon at the conclave of 1644 that elected Pope Innocent X. He was briefly Cardinal Deacon of Sant'Eustachio, before being raised to the order of Cardinal Priests in December 1644, with the title of San Sisto.
The next year, de' Medici was raised to Cardinal Bishop of Sabina, but opted for the suburbicarian see of Frascati seven months later. On 29 April 1652 he was made Cardinal Bishop of Porto e Santa Rufina and Vice-Dean of the College of Cardinals. On 23 September the same year he became Dean of the College of Cardinals and Cardinal Bishop of Ostia e Velletri. He presided over the conclave of 1655 and announced the papal election of Pope Alexander VII.[1]
Carlo de' Medici died in Florence in 1666. He is buried at his family crypt at the Basilica di San Lorenzo di Firenze.