PIO IV, POPE. – For more than four months the three factions of the Sacred College—the Spanish, the French, and the group of cardinals adhering to Paul IV—gathered in conclave and struggled among themselves, until on 25 December 1559, following the withdrawal of Cardinal Carafa, Gian Angelo Medici, the candidate of Duke Cosimo of Florence, was elected pope, taking the name PIO IV. He had been born in Milan to the notary Bernardino Medici on 31 March 1499; in 1525 he had earned his doctorate in utroque iure at Bologna and had demonstrated his administrative abilities during the pontificate of Paul III, serving as governor in Ascoli Piceno, Città di Castello, Parma, and Fano, as well as commissioner with the papal troops in Hungary and Transylvania, and finally as vice-legate of Bologna. From 14 December 1545 he was archbishop of Ragusa, and from 8 April 1549 a cardinal. Under Julius III he had played a certain, though modest, role as prefect of the Signatura gratiae, but owing to his pro-Spanish stance he had fallen into disfavour with Paul IV and had been obliged to spend most of his time outside Rome, in Tuscany and Milan. Highly esteemed as a jurist, he did not stand out as a political figure and even less could he be counted among the adherents of the ecclesiastical reform movement.
The political and ecclesiastical contrast between the new pope and his predecessor explains how Pio IV, from the very beginning of his pontificate, abolished or mitigated several laws and measures of Paul IV. Thus, for example, he abolished the severe bull issued against monks living outside their convents; he restricted the competences of the Roman Inquisition and began the revision of the Index librorum prohibitorum of 1559, which had proved unenforceable because of its severity. But above all he cultivated good relations with the Habsburg courts, not only with Philip II but also with Ferdinand I, and appointed nuncios to the nunciatures of Vienna, Venice, and Florence, which had remained vacant under Paul IV. With great severity he proceeded against the nephews of his predecessor: Cardinal Carlo Carafa and his brother Giovanni, Duke of Paliano, were condemned to death for treason and madness and also for the murder of the duke’s wife, and were executed on 5 March 1561, after Philip II of Spain refused to intercede on behalf of the condemned. Instead, Cardinal Alfonso Carafa and Cardinal Rebiba, who were in fact innocent, were pardoned and released. Of his many nephews the pope made cardinals: Carlo Borromeo, Gian Antonio Serbelloni, and Marco Sittich of Hohenems; while Federico Borromeo was married to Virginia della Rovere and proposed for the Duchy of Camerino, but died on 19 November 1562.
The principal concern of Pio IV was the improvement of religious conditions in France, where, after the death of King Henry II, the Calvinists, favoured by the vacillating policy of Queen Mother Catherine de’ Medici, were making rapid progress. The optimistic reports of the cardinal legate Ippolito d’Este did not create in Pio IV any illusions about the gravity of the situation, so that, to save France from the threat of Protestantisation, he convened the Council of Trent for the third time on 29 November 1560, ordering it to open on 18 January 1562. Like Paul III in the first period of the Council of Trent, Pio IV took pains to reform the authorities of the Curia, especially the Apostolic Chamber, the Sacred Rota, and the Penitentiary. Advised by Cardinal Morone, he intervened several times in the conciliar politics. He disapproved of the fact that the cardinal legates Ercole Gonzaga and Seripando had favoured the supporters of the *fus divinum* regarding the duty of episcopal residence and encouraged, both in the first dispute on this residence (April–May 1562) and during the great crisis of the Council (in the winter of 1562–63), the conciliar party of the *Zelanti*, of which the cardinal legate Simonetta, his trusted man, was the leader. When, after the arrival of the French, the great crisis of the Council took a dangerous turn because of the Emperor’s intervention, he—very likely on the advice of Cosimo I—won over to his conciliar policy, with a letter dated 1 April 1563 written in his own hand, King Philip II, and after the death of Cardinal Ercole Gonzaga he appointed his counsellor Morone as president of the Council. Morone, fully trusted by the pope, succeeded in winning over first Emperor Ferdinand I and then the leader of the opposition in the Council, the Cardinal of Lorraine, in favour of a negotiated solution to the conflict and a prompt conclusion of the Council. A dangerous illness that befell the pope at the end of November 1563 resulted in the final session being brought forward to 3 December 1563. Already on 26 January 1564, the pope, recovered, confirmed the Council unconditionally and immediately sought to implement its decrees. His nephew Carlo Borromeo set an example with his holy life and the reform of his archdiocese of Milan. On 2 August 1564 the pope granted certain powers to the commission of cardinals established to oversee the implementation of the reform decrees and to respond to questions about their meaning; from this commission there arose the Sacred Congregation of the Council. On 24 March 1564 he published the Index librorum prohibitorum prepared at Trent; on 13 November he prescribed to bishops and those who obtained benefices with cure of souls the recitation of the Tridentine Profession of Faith. On 16 April 1564, at the request of Emperor Ferdinand I and Duke William IV of Bavaria, he granted to the archbishops of Mainz, Cologne, Trier, Salzburg, Magdeburg, Bremen, and Gran (as well as to some other German and Austrian bishops) full faculty to administer Communion under both kinds to Catholics, provided they first confessed and professed the indivisible presence of Jesus Christ even under a single kind.
Some other tasks entrusted by the Council to the pope, such as the compilation of the Catechism and the reform of the Missal and the Breviary, were begun under Pio IV but not brought to completion.
The happy conclusion of the Council of Trent and the beginning of its implementation constitute the greatest achievement of Pio IV. Nevertheless, the movement of apostasy in the northern countries did not cease during his pontificate: in France the first War of the Huguenots broke out, in which the pope supported the Catholics with monetary subsidies; the attempt to bring Queen Elizabeth of England back to the Catholic Church ended in failure; in Germany Lutheranism spread more widely in the northern regions, while Calvinism took root in the south. Despite this, with the conclusion of the Council of Trent and the beginning of the implementation of its decrees, the foundations were laid for the Catholic Reformation, which was strengthened under the three successors of Pio IV, who took inspiration from the luminous example of his nephew Carlo Borromeo, whom Pastor rightly calls “the good genius” of his uncle.
The pope’s interest in the arts and sciences was manifested in the appointment of learned cardinals (e.g., Sirleto, Marcantonio Colonna, Hosius, Paleotti), and in the foundation of the Roman printing house through Paolo Manuzio. The pope’s finest architectural work is the Villa Pia in the Vatican Gardens and the well-known Porta Pia on the Via Nomentana. Pio IV died on 9 December 1565; his remains were transferred in 1583 to the church of Santa Maria degli Angeli, which he had restored. – See pl. CII.