A period of renewed power for the papacy began in the year 1420, when Pope Martin V (r. 1417–31) moved the papal seat back to Rome, following its long “Babylonian Captivity,” when it was based at Avignon, France (1309–77), and after the Great Schism (1378–1417), when several “popes” simultaneously claimed the office. This resurgence continued until 1527, when Holy Roman Emperor Charles V (r. 1519–56) sacked Rome, driving away many artists and disrupting papal power.
Though Rome had agricultural strength, it was not a commercial or banking center. The prosperity of the papacy depended, therefore, on its home markets, which was comprised of thousands of church bureaucrats and visiting pilgrims. More than 100,000 pilgrims flooded the city in some Jubilee years. (These special years, when one could receive a full pardon for sins during a visit to Rome, occurred once every twenty-five years, starting with the reign of Pope Paul II [r. 1464–71].) To secure Rome and its Papal States—the territories that the papacy controlled in central and northern Italy and southern France—popes became heavily involved in temporal matters, even leading armies, as was the case with the very worldly Pope Julius II (r. 1503–13).
During these years, popes strove to make Rome the capital of Christendom while projecting it, through art, architecture, and literature, as the center of a Golden Age of unity, order, and peace. Papal officials came from many nations to promote a united Church. Humanists in Rome, many of them foreign clerics involved with theology and some of them popes , studied all aspects of antiquity, edited its texts , and, under the influence of classical models, produced poems, plays, and new rhetorical genres such as the panegyric. Since many antiquities were unearthed in or near Rome, popes were well situated to become serious collectors of ancient art; Julius II, for instance, took charge of both the Apollo Belvedere and Laocoön sculptures after they came to light. After Nicholas V (r. 1447–55) moved the papacy from the Lateran Palace to the Vatican Palace, he and his successors constructed or rebuilt fortifications, streets, bridges, and piazzas to ensure safe access to the Vatican area for pilgrims and processions. Looking to imperial Rome as a model, they conceived building and art projects to be political statements, and the best architects and artists congregated in Rome to achieve them, such as Leon Battista Alberti (1404–1472). “Not for ambition,” Nicholas V said on his deathbed, “nor pomp, nor vainglory, nor fame, nor the eternal perpetuation of my name, but for the greater authority of the Roman church and the greater dignity of the Apostolic See… we conceived such buildings in mind and spirit.”
Notwithstanding, popes frequently made the glorification of themselves and their families a high priority. Rather than extend the work of their predecessors, they often sponsored personal projects, including lavish palaces and tombs for themselves and their relatives. Pope Pius II (r. 1458–64) even had his birthplace, the Tuscan hamlet of Corsignano, rebuilt under the direction of the famous Florentine architect Bernardo Rossellino (1407/10–ca. 1464). (Pius renamed the town Pienza around 1462.) In such an environment, corruption became rampant. For instance, Pope Sixtus IV (r. 1471–84), a Franciscan who came from a poor family, led a blameless personal life and was a great supporter of scholarship and the arts, but he was also guilty of the worst sort of nepotism, which spurred political unrest in Italy, financial confusion in the papacy, and a neglect of the spiritual interests of the Church.
Along with this, other aspects of papal worldliness fueled a long-standing discontent with the Church that culminated in the Reformation. The military exploits of Julius II have already been mentioned. But it was the granting of indulgences—the temporal remission of punishment in Purgatory—by Julius II and Leo X (r. 1513–21) to those who would give money to help rebuild Saint Peter’s in Rome that spurred Martin Luther to post his 95 Theses on the door of the Schlosskirche in Wittenberg in 1517. The ensuing controversy, in which Luther denied the authority of Rome and asserted that salvation came through faith in Christ alone, brought about a permanent rupture in Western Christendom.