Pope Pius II (1405-1464)

The Humanist Who Became Pope

No pope has embodied so fully the sometimes explosive encounter between the Renaissance and the papacy. Piccolomini was first and foremost a man of letters: he knew Virgil, Cicero, and the Greeks, wrote elegant Latin, and frequented the humanist circles of Florence and Siena.^[12][13] Raised to the tiara, he brought this culture to the pinnacle of the Church—but he also renounced it, aware that the worldly poet and the vicar of Christ could not be the same man. His figure poses, better than any other, the question of the relationship between worldly wisdom and faith: can one serve God with the weapons of the humanists?

The Pope Who Broke Conciliarism

Pius II’s second claim to fame—or notoriety—is doctrinal. Since the Council of Constance (1414–1418) and the Great Western Schism, part of the West held that the general council was superior to the pope.^[14][15] Piccolomini himself had defended this thesis at Basel. As Pius II, he struck it down with anathema by the bull Execrabilis: no one may, under penalty of excommunication, appeal from the pope’s judgment to a future council. This is one of the most decisive acts in the restoration of Petrine primacy on the threshold of the modern era—a deed confirmed by the entire Catholic tradition.^[16]

The Last Great Crusader

Finally, Pius II is, in the consecrated phrase, the pope of the last pontifical crusade of the medieval type led by a pope in person. Where his predecessors had issued calls that went unanswered, he wished to take the cross himself, old and crippled, and personally lead the expedition.^[17][18] The effort failed: the princes balked, the fleet was delayed, and death caught him in Ancona. But this devotion to the end, this almost chivalrous obstinacy of a scholar turned soldier of the faith, gives his pontificate its tragic grandeur. With him, it is often said, the medieval ideal of the crusade dies out.

A Unique Case: The Pope Who Wrote His Own Life

Pius II enjoys a privilege that no other pope possesses: he left his autobiography. His Commentarii rerum memorabilium ("Commentaries on Memorable Things"), written in thirteen books during his pontificate, are the only autobiography ever written by a reigning pope.^[19][20] He recounts everything — his childhood, his embassies, the conclave that elected him, his travels, the beauty of the Tuscan landscapes, his disillusionments with princes. It is a first-rate document, but also a defense: Pius II portrays himself as he wished to be seen. The historian must read it with admiration and caution.

Table of Witnesses

The table below summarizes the main sources documenting the life of Pius II and the caution required for each.

Bulls, Orations, and Modern Notices

Beyond the autobiography, the pontificate is documented by its acts: the bull Vocavit nos convening Mantua (1458), the bull Execrabilis (1460), the bull of retraction (1463), the crusade bull Ezechielis prophetae (1463).^[21][22][23] Pius II was also a famous orator: his speeches, such as the great oration Cum bellum hodie delivered at Mantua in 1459, circulated throughout Europe.^[24] For critical framework, the reference notices — Enciclopedia dei Papi from Treccani, Catholic Encyclopedia, Encyclopaedia Britannica — and the biographies by Cecilia Ady and Ludwig von Pastor remain foundational works.^{[25][26][27][28][29]}

A Noble but Ruined Birth in Corsignano

Enea Silvio Piccolomini was born on October 18, 1405, in Corsignano, a small village in the Val d'Orcia, within the territory of Siena.^[30][31] He was the eldest of eighteen children of Silvio Piccolomini and Vittoria Forteguerri. The Piccolomini were a great noble family of Siena, related to the Tolomei — but they had been excluded from power since 1385, when the noble party was expelled from the city, and Enea’s father lived in semi-ruin in the countryside.^[32] The child thus grew up with a dual awareness: that of illustrious blood and that of lost fortune. Everything in his life would be a reconquest.

The Student of Siena and Florence

At eighteen, around 1423, Enea was sent to study law at the University of Siena; but he soon abandoned jurisprudence for classical letters, his true passion.^[33][34] In 1429, he went to Florence to attend Greek lessons from the famous humanist Francesco Filelfo; there he mingled with Leonardo Bruni and Poggio Bracciolini, masters of early humanism. Returning to Siena, he studied canon law under the great jurist Niccolò Tedeschi (the "Panormitan"). From this dual education — humanist and legal — emerged the complete man: the scholar who also knew how to handle affairs and chancelleries.

Secretary of the Council of Basel

His public career began at the Council of Basel, where he arrived in spring 1432 as secretary to Cardinal Domenico Capranica.^[35][36] The council, opened in 1431, increasingly opposed Pope Eugene IV, in the name of the superiority of the council over the pope. The young Piccolomini threw himself into it with zeal: he became one of the most committed supporters of the conciliarist thesis, climbed the ranks of the conciliar bureaucracy — writer, abbreviator, then chief abbreviator — and was noticed on November 16, 1436, by a speech that established him as a talented orator.^[37] Along the way, he served several prelates and undertook distant missions, including a secret embassy to Scotland (1435) that nearly cost him his life in a storm and gave him the gout from which he suffered all his life.^[38]

Supporter of Antipope Felix V

Piccolomini’s commitment reached its extreme when the rebellious phase of the Council of Basel deposed Eugene IV and elected, on November 5, 1439, an antipope: Amadeus VIII of Savoy, under the name Felix V.^[39][40] Enea attended the election, entered the service of the antipope as secretary, and even wrote in 1440 a Libellus to defend the legitimacy of Felix V.^[41] This was the height of his youthful error: he took sides, by pen and office, against the legitimate pope of the Church. He would bitterly repent, and all his pontifical policy would, in a sense, be the repair of this fault.

Poet Laureate of Frederick III

In 1442, his life shifted for the first time. Weary of Basel, he entered the service of the King of the Romans Frederick III of Habsburg. On July 27, 1442, in Frankfurt, the emperor crowned him poet laureate — the highest humanist distinction — then attached him to his imperial chancery.^[42][43] Settled in Wiener Neustadt as secretary, Piccolomini became the Empire’s most brilliant diplomat. It was there that he would negotiate, a few years later, the Concordat of Vienna (1448) which regulated relations between the Church and Germany.^[44]

Secular Writings: Chrysis and The Two Lovers

These court years were also those of his worldly writings, which he would later renounce. In 1444, he composed a licentious comedy in the ancient style, Chrysis; in 1444, a love novel, De duobus amantibus historia ("History of the Two Lovers"), which enjoyed immense success and was one of the first bestsellers of the nascent printing press.^[45][46] He also wrote a satirical treatise, De curialium miseriis ("On the Miseries of Courtiers"), and numerous poems. This lively, brilliant, and profane production long made Enea Silvio famous — and would become, for Pope Pius II, a burden to bear.

Conversion to the Roman Cause (1445)

In spring 1445, Piccolomini was sent on an embassy to Rome to meet Eugene IV. There, before the pope, he made a decisive gesture: he publicly renounced the conciliar cause and rallied to the Apostolic See.^[47][48] Absolved of the excommunication incurred, he henceforth put his diplomatic genius at the service of reconciliation between the Empire and Rome. This conversion was not only political: it marked the beginning of an inner turnaround. The worldly man of letters slowly turned toward the priesthood and a more serious life.

From Subdeacon to Cardinal (1446-1456)

His rise was then rapid. Ordained subdeacon in the spring of 1446, then priest on March 4, 1447, at the age of forty-one, Piccolomini was appointed that same year bishop of Trieste, then, in 1450, bishop of Siena, his hometown.^[49][50] Tireless diplomat for Eugene IV and then Nicholas V, he prepared the imperial coronation of Frederick III (1452) and wove his network everywhere. In recognition of his services, Pope Callixtus III made him a cardinal on December 17, 1456, with the titular church of Santa Sabina.^[51] Less than two years later, the conclave would make him pope.

The Conclave after Callixtus III

Callixtus III died on August 6, 1458. The conclave opened on August 16, gathering eighteen cardinals out of twenty-four.^[52][53] Pius II left, in his Commentarii, a striking and unparalleled account: the nocturnal negotiations, promises, the maneuvers of the powerful French cardinal Guillaume d'Estouteville to buy votes, and the resistance of Piccolomini’s supporters.^[54] It is one of the rare conclaves in history recounted from the inside by the elected pope himself. On August 19, 1458, after two ballots, Aeneas Silvius prevailed by gaining the votes and became pope.

The Choice of the Name Pius

Elected, Piccolomini chose a name heavy with meaning: Pius, Pius. The choice was not devotional but literary as much as spiritual: it echoed the hero of Virgil, the pius Aeneas, “the pious Aeneas,” who bore the same first name as him.^[55][56] The humanist remained true to himself even in his papal name—but transforming it: the poet’s profane “Aeneas” became the pontiff’s “Pius.” He was crowned on September 3, 1458. The program of the new reign was clear in his mind: to save Christendom threatened by the Turks.

The Shadow of Constantinople

Pius II’s entire pontificate was dominated by a catastrophe that occurred five years before his election: the fall of Constantinople to Mehmed II on May 29, 1453.^[57][58] The fall of the city of Constantine shocked the West; a Turkish tide onto Italy itself was now feared. Pius II made the response the cause of his life. As early as October 13, 1458, by the bull Vocavit nos, he summoned the Christian princes to a great congress at Mantua to organize the crusade.^[59]

The Congress of Mantua (1459)

Pius II left Rome on January 22, 1459, and after a long journey through Siena and Florence, solemnly opened the Diet of Mantua on June 1, 1459.^[60][61] There, on September 26, he delivered one of his most famous orations, Cum bellum hodie, a passionate call for the unity of Christendom against the conquering Islam.^[62] But the experience was a bitter trial: the pope arrived first and waited months for princes who hesitated, came late, or sent only ambassadors charged with bargaining for particular advantages.

“We spent many sleepless nights reflecting on it, and turning in our bed, we were in despair.” — Pius II, on organizing the crusade, Commentarii^[63]

The Failure of the Christian Princes

The Congress of Mantua ended in a partial failure. On paper, a three-year crusade and subsidies were voted; but no sovereign truly committed. France, the Empire, Burgundy, Venice—all had their own calculations; the unity of Christendom that Pius II dreamed of already belonged to the medieval past.^[64][65] The pope understood that if he wanted a crusade, he would have to lead it himself—an old, sick man taking command of the armies of the faith, for lack of princes to do so.

The Letter to Mehmed II

Among the most singular gestures of his pontificate was a long letter addressed to Sultan Mehmed II, the Epistola ad Mahomatem, written around 1461.^[66][67] Pius II invited the conqueror to convert to Christianity and be baptized, promising to recognize him as the greatest prince of Christendom. The letter, probably never sent, is in fact a treatise of apologetics and political strategy, presenting to the sultan, through reason and history, the superiority of the Christian faith. It testifies to the spirit of the humanist, convinced that the word could triumph where armies delayed.

The Alum of Tolfa: “Victory over the Turk”

Providence seemed to smile on him for a moment. In 1462, one of his close associates, Giovanni di Castro, discovered in the volcanic hills of Tolfa, near Rome, vast deposits of alum—a mineral essential for dyeing cloth, which until then had been imported from the Turks at great expense.^[68] The discovery deprived the enemy of a resource and enriched the papal treasury.

“Today I bring you victory over the Turk. These hills will give you the sinew of war, that is to say money, while taking it away from the Turks.” — Giovanni di Castro to Pius II, about the alum mines of Tolfa^[69]

Pius II allocated the alum revenues to the crusade: the wealth of Tolfa became, for decades, one of the major sources of funding for the Apostolic Chamber.

The Bull of January 18, 1460

At the heart of the pontificate lies a crucial doctrinal act. On January 18, 1460, Pius II promulgated the bull Execrabilis, named after its opening word.^[70] It condemns, as an “execrable and unheard-of abuse in ancient times,” the practice of appealing from the judgment of the pope to a future general council. Whoever dares such an appeal incurs anathema, which only the pope can absolve, and only at the point of death.

“We condemn such appeals and reject them as erroneous and detestable.” — Pius II, bull Execrabilis, January 18, 1460^[71]

The gesture is full of meaning: it is the former conciliarist of Basel who now forbids the very thesis he once defended. Execrabilis is one of the great acts of the reconstruction of pontifical authority after the Great Schism; Catholic tradition has seen in it the solemn reaffirmation of the primacy of the successor of Peter over any assembly.

“Reject Aeneas, Welcome Pius”: The Retraction of 1463

Three years later, Pius II went even further and confronted his own past. By the bull In minoribus agentes (“When we were in a lower rank”), dated April 26, 1463 and addressed to the rector and the University of Cologne, he solemnly retracted, in a personal capacity, his youthful writings favorable to the Council of Basel and antipope Felix V.^[72] With famous humility, he asked that the man he once was be distinguished from the pope he had become:

“Many things now displease us that, when younger, we had approved. Do not regard the private man more than the pontiff: reject Aeneas, welcome Pius.” — Pius II, In minoribus agentes, April 26, 1463^[73]

This rare public confession from a sovereign pontiff seals the internal coherence of his reign: Execrabilis condemned the doctrine, the retraction condemned the author. The pope had triumphed over the humanist.

Pienza, the Ideal City

Pius II never forgot his native village. He decided to make it an ideal city, a model of Renaissance urbanism, and renamed it after himself: Pienza, “the city of Pius.”^[74] The Florentine architect Bernardo Rossellino, perhaps advised by Leon Battista Alberti, directed the works from 1459: around a harmonious square rose the cathedral — consecrated by the pope on August 29, 1462 — the Palazzo Piccolomini, and the episcopal palace. Pienza is considered the first application of humanist urban planning principles; its center is now a UNESCO World Heritage site.^[75] In this golden stone of the Val d’Orcia, the humanist turned pope left his dream of Christian beauty.

The Canonization of Saint Catherine of Siena

Pius II also honored the great saint of his homeland. In 1461, he canonized Catherine of Siena (1347–1380), the Dominican mystic who had worked for the return of the popes from Avignon to Rome.^[76][77] The choice is revealing: by elevating to the altars the woman who had served the unity of the Church and the dignity of the Apostolic See a century earlier, the Sienese pope inscribed his own struggle — against schism and conciliarism — in a long spiritual lineage. Catherine would later become a Doctor of the Church and patroness of Italy and Europe.

Defender of Rome and Its Relics

A humanist enamored with Antiquity, Pius II was among the first to care about the preservation of Rome’s ancient monuments: by the bull Cum almam nostram urbem (April 28, 1462), he forbade the demolition and pillaging of Roman ruins to make lime.^[78] He also enriched the spiritual treasure of the City: in 1462, he solemnly welcomed to Rome the relic of the head of Saint Andrew, saved from Greece before the Turkish advance, and delivered a famous speech on the occasion. The learned pope knew that memory, both sacred and secular, was a heritage to be defended.

The Final Journey

Lacking princes willing to act, Pius II resolved to take the cross himself. Old, exhausted by gout and fever, he left Rome on June 18, 1464 for Ancona, on the Adriatic, where the crusading fleet was to assemble.^[79] He arrived there on July 18, in a city overcrowded and ravaged by plague, and waited for ships that never came. When the Venetian fleet under Doge Cristoforo Moro finally appeared offshore on August 12, the dying pope could only watch it from his bedroom window.

“Woe to you, woe to you if you abandon the work of God!” — exhortation of Pius II to his cardinals gathered around his bed, on August 13, 1464, on the eve of his death at Ancona^[80]

On August 14, 1464, two days after seeing the fleet, Pius II breathed his last.^[81][82] With him died, in the consecrated phrase, the last pontifical crusade of the medieval type led by a pope in person: the later expeditions — Otranto in 1481 under Sixtus IV, the Holy League and Lepanto in 1571 under Saint Pius V — were no longer led by a pope personally taking the cross.^[83] His body was brought back to Rome and buried at Saint Peter’s, near the relic of Saint Andrew; in 1614 it was transferred to the church of Sant'Andrea della Valle, where his tomb now rests.

A Timeline of the Pontificate

The Successor: Paul II

Pius II was succeeded by the Venetian cardinal Pietro Barbo, who took the name Paul II (1464–1471).^[84] Less learned than his predecessor and sometimes at odds with the humanists of the Curia, Paul II abandoned the grand crusading project to which Pius II had devoted his life. The Sienese Piccolomini dynasty would, however, produce another pope: Pius II’s nephew, Francesco Todeschini Piccolomini, who reigned briefly in 1503 as Pius III.

What to Remember About Pius II?

Pius II holds a unique place in the history of the papacy. He was the greatest humanist ever to ascend the throne of Peter, and one of those who most firmly restored its authority.^[85][86] His life united extremes that seem irreconcilable: the worldly poet and the reforming pope, the conciliarist of Basel and the author of Execrabilis, the skeptical scholar and the crusader who died at Ancona. This unity, recovered despite so many contradictions, is precisely what makes him a fascinating figure — a man of a single successful renunciation, that of himself for the sake of God.

The Spiritual Lesson: The Conversion of a Life

Pius II’s deepest legacy is neither Execrabilis, nor Pienza, nor the failed crusade: it is the example of a conversion. Here is a man who had everything to succeed by worldly standards — talent, literary fame, intellect, success — and who, having reached the summit, had the courage to publicly renounce what had made him shine, to serve only the Church. “Reject Aeneas, welcome Pius” is not a phrase of pride, but an act of humility: the recognition that a man can be wrong for a long time, and that grace can set an entire life aright.

His crusade failed, his contemporaries faltered, his fleet arrived too late. But the old gout-ridden pope who stubbornly waited to die facing the sea at Ancona, awaiting ships that would never sail, offers the image of a faithfulness that no longer calculates. “Seek first the kingdom of God” (Mt 6:33): Pius II, who had long sought other things, ended by seeking nothing else. This is why the humanist pope, despite his shadows, remains a great spiritual figure of the late Middle Ages.

• Pope Callixtus III — predecessor of Pius II, the first Borgia pope, who made him a cardinal and already called for a crusade.
• Pope Nicholas V — the first Renaissance pope, whose patronage and fight against the Turks Pius II continued.
• The Fall of Constantinople (1453) — the Eastern disaster that overshadowed Pius II’s entire pontificate.
• The Western Schism — the long division whose conciliarism at Basel was its final extension, condemned by Execrabilis.
• The Christian Renaissance — the cultural movement of which Pius II was one of the most illustrious representatives, even from the papal throne.
• The Decline of the Borgia Popes — the house of his predecessor Callixtus III and his distant successor Alexander VI.