Pietro Carnesecchi. — Heretic, born in Florence on 24 December 1508, beheaded in Rome on 1 October 1567. Son of a noble Florentine merchant and a connoisseur of Greek and Latin letters, he quickly won the esteem of the Medici, especially Cardinal Giulio, who, upon becoming Pope Clement VII, took him to Rome as his secretary and provided him with rich ecclesiastical benefices. In a letter of recommendation to Charles V (27 June 1531), Clement described him as “a man of the utmost loyalty and singular modesty, whom I love so much for his merits and devoted spirit towards me, as well as for his virtue and nobility, that I could not love him more.”
In 1533, alongside Clement VII, he attended the conference of Marseille. In Naples, Giulia Gonzaga—whom he esteemed and loved—introduced him to Juan de Valdés, Bernardino Ochino, Pietro Martire Vermigli, and other more or less open advocates of reform in Italy (1536–40). By 1541 he was in Viterbo, where a circle of “spirituals” formed around the English cardinal Reginald Pole; though remaining within the Church, they leaned toward Lutheranism, particularly in their emphasis on justification by faith alone. The apostasy of Ochino and Vermigli in 1542 alarmed Church authorities about the danger of these currents. Carnesecchi, though in contact with both foreign and Italian heretics, managed to conceal his own views and was acquitted by the Roman Inquisition for lack of evidence (1546).
He then went to France as a guest of Catherine de’ Medici, his protector and friend. In 1552 he moved to Venice, increasingly manifesting his sympathy for reform. Pope Paul IV summoned him to Rome in 1557, but Carnesecchi refused to appear and was condemned *in absentia* on 6 April 1558. Upon the death of Paul IV, he reappeared in Rome, had his case reopened, and—describing the earlier condemnation, as Pius V would later say, as “a mountain of lies”—obtained its annulment (June 1560). Yet suspicions persisted, and his conduct did little to dispel them. Pius V ordered a new trial. At the time, Carnesecchi was with Cosimo de’ Medici, who, at the Pope’s request, surrendered him (July 1566). The trial lasted a year; instead of confessing and recanting—relying on the protection of Cosimo and Catherine de’ Medici—he insisted on defending himself. As the evidence against him mounted, he was finally condemned on 21 September 1567, beheaded on 1 October 1567, and then burned.