Pope Pius V, OP (Italian: Pio V; 17 January 1504 – 1 May 1572), born Antonio Ghislieri (and from 1518 called Michele Ghislieri), was head of the Catholic Church and leader of the Papal States from 7 January 1566 to his death, in May 1572.
He was an inquisitor and is venerated as a saint of the Catholic Church. He is chiefly notable for his role in the implementation of the Council of Trent, the Counter-Reformation, and the standardization of the Roman Rite within the Latin Church, known as the Tridentine Mass. Pius V declared Thomas Aquinas a Doctor of the Church.
As a cardinal, Ghislieri gained a reputation for putting orthodoxy before personalities, prosecuting eight French bishops for heresy. He also stood firm against nepotism, rebuking his predecessor Pope Pius IV to his face when he wanted to make a 13-year-old member of his family a cardinal and subsidize a nephew from the papal treasury.
By means of the papal bull of 1570, Regnans in Excelsis, Pius V excommunicated Elizabeth I of England for heresy and persecution of English Catholics during her reign. He also arranged the formation of the Holy League, an alliance of Catholic states to combat the advancement of the Ottoman Empire in Eastern Europe. Although outnumbered, the Holy League famously defeated the Ottomans at the Battle of Lepanto in 1571. Pius V attributed the victory to the intercession of the Blessed Virgin Mary and instituted the feast of Our Lady of Victory. Biographers report that as the Battle of Lepanto ended, Pius rose and went over to a window, where he stood gazing toward the East. "...[L]ooking at the sky, he cried out, 'A truce to business; our great task at present is to thank God for the victory which He has just given the Christian army'."
Antonio Ghislieri was born 17 January 1504, to Paolo Ghislieri and Domenica Augeri, in Bosco in the Duchy of Milan (now Bosco Marengo in the province of Alessandria, Piedmont), Italy. At the age of fourteen he entered the Dominican Order, taking the name Michele, passing from the monastery of Voghera to that of Vigevano, and thence to Bologna. Ordained a priest at Genoa in 1528, he was sent by his order to Pavia, where he lectured for sixteen years. At Parma he advanced thirty propositions in support of the papacy and against Protestantism.
He became master of novices and was on several occasions elected prior of more than one Dominican priory. During a time of great moral laxity, he insisted on discipline, and strove to develop the practice of the monastic virtues. He fasted, did penance, passed long hours of the night in meditation and prayer, traveled on foot without a cloak in deep silence, or only speaking to his companions of the things of God. As his reformist zeal provoked resentment, he was compelled to return to Rome in 1550, where, after having been employed in several inquisitorial missions, he was appointed to the commissariat of the Holy Office.
In 1556 he was made Bishop of Sutri by Pope Paul IV and was selected as inquisitor of the faith in Milan and Lombardy. In 1557 he was made a cardinal and named inquisitor general for all Christendom. His defense of Bartolomé Carranza, Archbishop of Toledo, who had been suspected of heresy by the Spanish Inquisition, earned him a reprimand from the pope.
Under Pope Pius IV (1559–65) he became Bishop of Mondovì in Piedmont. Frequently called to Rome, he displayed his unflinching zeal in all the questions on which he was consulted. Thus he offered opposition to Pius IV when the latter wished to make Ferdinand de' Medici, then only thirteen years old, a cardinal. His opposition to the pontiff led to his dismissal from the palace and limits being placed on his authority as inquisitor.
Before Michele Ghislieri could return to his diocese, Pope Pius IV died. On 4 January, a courier from Spain arrived, prompting rumors that King Philip II favoured the election of Cardinal Ghislieri. This in turn gave additional momentum to the efforts of Cardinal Charles Borromeo and his allies, who already supported the candidacy of Ghislieri. As the cardinals conferred with each other more intensely, the number of those who looked to Ghislieri increased, and this led eventually to his election as the new pope on the afternoon of 8 January 1566. Ghislieri took the regnal name Pope Pius V. He was crowned ten days later, on his 62nd birthday, by the protodeacon.
Six weeks after the conclave, Cardinal Borromeo wrote to Cardinal Henry of Portugal recalling the election. He spoke of the new pope, and of his "high esteem for him on account of his singular holiness and zeal", seeing these qualities as a sign that he would make a good pope "to the great satisfaction of all".
His pontificate saw him deal with internal reform of the Church, the spread of Protestant doctrines in the West, and Turkish armies advancing from the East.
Aware of the necessity of restoring discipline and morality in Rome to ensure success, he at once proceeded to reduce the cost of the papal court after the manner of the Dominican Order to which he belonged, compel residence among the clergy, regulate inns, and assert the importance of the ceremonial in general and the liturgy of the Mass in particular.
In his wider policy, which was characterized throughout by an effective stringency, the maintenance and increase of the efficacy of the Inquisition and the enforcement of the canons and decrees of the Council of Trent had precedence over other considerations.
In March 1571, he created the Congregation of the Index to formalize the censorship of books deemed heretical or immoral.
Accordingly, to implement a decision of that council, he standardized the Mass by promulgating the 1570 edition of the Roman Missal. Pius V made this Missal mandatory throughout the Latin Church, except where a Mass liturgy dating from before 1370 was in use. This form of the Mass remained essentially unchanged for 400 years until Pope Paul VI's revision of the Roman Missal in 1969–70, after which it has become widely known as the Tridentine Mass.
Pius V, who had declared Thomas Aquinas the fifth Latin Doctor of the Church in 1567, commissioned the first edition of Aquinas' opera omnia, often called the editio Piana in honor of the Pope. This work was produced in 1570 at the studium generale of the Dominican Order at Santa Maria sopra Minerva, which would be transformed into the College of Saint Thomas in 1577, and again into the Pontifical University of Saint Thomas Aquinas, Angelicum in the 20th century.
Pius V arranged the forming of the Holy League against the Ottoman Empire, as the result of which the Battle of Lepanto (7 October 1571) was won by the combined fleet under Don John of Austria. It is attested in his canonisation that he miraculously knew when the battle was over, himself being in Rome at the time. Pius V also helped financially in the construction of Valletta, Malta's capital city, by sending his military engineer Francesco Laparelli to design the fortification walls (A bronze bust of Pius V was installed at the Gate of Valletta in 1892.) To commemorate the victory, he instituted the Feast of Our Lady of Victory.
By the time Pius V ascended the throne, Protestantism had swept over all of England and Scotland, as well as half of Germany, the Netherlands, and parts of France; only Spain, Ireland, Portugal and Italy remained unswervingly Catholic. Pius V was thus determined to prevent its insurgency into Italy—which he believed would come via the Alps and Milan.