Sixtus IV

August 9, 1471 - August 12, 1484





The pontificate of Pope Sixtus IV benefited the arts and the city of Rome but created much political and military conflict in many parts of Italy.  Sixtus' nepotism and use of bribery defined a new low of corruption.  He ultimately paid for his excessive spending by selling indulgences (forgivenesses), which prompted much public dissatisfaction and was one of the complaints cited by the founders of the Reformation.


Family and Birthplace

Pope Sixtus IV was born Francesco della Rovere in 1414 in Celle, a town near Savona.  Unlike most men who rise to the level of pope, Sixtus was from a poor family.


Affiliation with Franciscan Order

Francesco was educated by the Franciscan Order, which he joined as a young man.


Francesco studied theology at the Universities of Bologna and Padua.  In the decades before his election as a cardinal in 1467 at the age of 53, Francesco distinguished himself as a preacher, a theologian, and a university lecturer.


In 1464, Francesco was elected Minister general of the Franciscan Order.


Election as Pope

Several factors made Francesco's election possible in spite of his having been a cardinal for only four years.


The sudden and unexpected death of his papal predecessor, Paul II, deprived would-be candidates of the lead time necessary to form coalitions of supporters.


Bribing cardinals, who formed the electorate, with promises of lucrative benefices and other favors was critical to Francesco's election.


The support of Galeazzo Maria Sforza, the Duke of Milan, also contributed to Francesco's election.  The pope later made the duke's younger brother, Ascanio Sforza, a cardinal.





Crusade Attempt in 1472

When Sixtus first came to power, he sent cardinals to persuade the rulers of Europe to send forces for a crusade against the Turks, who had overthrown the Christians in Constantinople in 1453.  Previous crusades had failed, and the European states declined to help.  In the end, Sixtus sent a small force from Naples and Venice.  They landed at Smyrna but soon disbanded, having made no impact on the Turkish presence in Asia Minor.


Conflict with Louis XI of France

King Louis XI (1461-83) of France upheld the "Pragmatic Sanction of Bourges," a resolution requiring royal approval for the publication of papal decrees in France.  In 1475, Louis issued an ordinance affirming this position, and the relationship between him and the pope remained tense.


Establishment of the Spanish Inquisition

Sixtus ceded to the request of King Ferdinand of Aragon and Queen Isabella of Castile to establish an inquisition in Spain to deal with heretics.  He also affirmed the appointment of the infamous grand inquisitor Tomas de Torquemada (1420-98).


The Spanish Inquisition quickly evolved into a convenient means of controlling political opposition, and the abuses were so egregious that even the pope called for greater restraint.  Many of those found guilty of heresy were sentenced to being burned alive.


Attempted Unification with Eastern Church

Pope Sixtus revived a plan favored by his predecessor, Paul II, to reunite the Roman Catholic Church and Eastern Orthodox Church.  The union was to have been symbolized by a marriage between Ivan III of Russia and the niece of John VIII Palaeologus.  Although the marriage took place, the hoped for unification of the Churches did not.


Fall of Otranto and 1481 Crusade

In 1480, the Turks, who were led by Sultan Mehmet II, conquered Otranto, the easternmost port of Italy, and killed much of the population.


In 1481, Pope Sixtus called for a crusade and raised forces from Venice and Hungary.  Following the sudden death of the Sultan in 1482, the Turks withdrew.






The pope's involvement in factional politics, which was much influenced by his nephew Girolamo Riario, was motivated by his desire to increase his control over the Papal States and add to his territory at the expense of his neighbors.  To this end, he instigated warfare among the larger states of Italy and was probably aware of the plot to overthrow the Medici, who controlled Florence.


Acquisition of Imola

Pope Sixtus expanded the Papal territory in central Italy by buying the fiefdom of Imola from Duke Galeazza Sforza. Lorenzo the Magnificent, who controlled not only Florence but much of the neighboring territory, opposed this escalation in papal power and called upon other Florentine bankers not to loan him the money.  The Pazzi financed the transaction, and the pope rewarded them with papal accounts and the right to mine alum, which was needed in the dyeing process of Florence's textile industry.


The Pazzi Conspiracy

The ill feelings generated by the pope's acquisition and financing of Imola contributed to the confrontation between the Pazzi and the Medici  known as the Pazzi Conspiracy. The extent of the pope's involvement is unknown, but because his nephew Girolamo Riario is known to have been in on the plot, it is assumed that he knew of it.


The plot's failure led to the execution of several members of the Pazzi and Salviati families including Francesco Salviati, whom Sixtus had appointed as the Archbishop of Pisa.  They were hung from the Palazzo della Signoria, which is now called the Palazzo Vecchio.


In retaliation, Sixtus excommunicated Lorenzo, interdicted Florence, and encouraged King Ferdinand I of Naples to attack Florence.  Lorenzo's visit to Naples prevented the latter, and the situation was resolved in 1480 by a larger threat to them both--the invasion of the Turks on the Italian peninsula.


Factional Politics

In an effort to gain more territory, the pope incited Venice to attack Ferrara, a powerful neighbor of Imola.  Naples entered the war in defense of Ferrara but was defeated by Venice in 1482.  Sixtus, who then feared Venice's strength, switched to Ferrara's side and interdicted Venice in 1483.  Such political maneuvering undermined the stability of the Italian states and damaged the pope's reputation.






Sixtus IV engaged in corrupt practices to enrich his family, live like a king, and make extravagant commissions.


Bribing Cardinals to Elect Him Pope

To gain their support in his election to the papacy, Francesco bribed cardinals with promises of lucrative appointments.


Appointing Relatives to High Offices

As Pope Sixtus IV, Francesco established the della Rovere family by advancing family members both in the Church and in government.


Pope Sixtus bestowed cardinalships on all of his unmarried nephews and grand nephews who were old enough to hold office and loaded them with lucrative benefices (ecclesiastical offices with income sources).  His nephew Giuliano della Rovere later became Pope Julius II, and he, in turn, appointed four della Rovere cardinals from the next generation.


For married nephews and the husbands of his nieces, Sixtus arranged titled positions in Rome and elsewhere under his control.  For instance, he elevated his nephew Girolamo Riario to the rank of count (between a duke and a marchese), arranged for him to marry a daughter of Duke Galeazzo Maria Sforza of Milan, and made him governor of Imola, which lay to the north of Florence.


Allowing Church Property to be Inherited

Pope Sixtus changed the inheritance laws concerning the property of popes and cardinals.  Instead of passing to the Church at their deaths, properties acquired and improved by popes and cardinals while serving the Church could be passed on to their families.


Appointing Unqualified Cardinals

Sixtus' naming of 34 cardinals nearly doubled the size of the College of Cardinals and flooded it with unqualified men who returned the favor by supporting the pope's policies.  The packing of the College of Cardinals with members who were less qualified and more worldly led to greater secularization of the Church because the popes they subsequently elected were less concerned with fulfilling the Church's spiritual mission than with living like princes.


Selling Indulgences

To raise money, Pope Sixtus authorized the sale of Indulgences, forgivenesses that were formerly granted by the clergy without charge.  The selling of indulgences was one of the practices that incited Martin Luther to publicly call for reforms in the next century.





Promoting Franciscan Beliefs

Pope Sixtus promulgated certain values and beliefs held by the Franciscans by his power to celebrate saints and events.


Limiting representation of stigmata. The pope ruled that only St. Francis, the founder of the Franciscan order, could be depicted with the stigmata, his main attribute.  


Canonization of Bonaventura. In 1482, Sixtus canonized Bonaventura, a distinguished thirteenth century theologian of the Franciscan order.  


Promoting belief in Immaculate Conception. Sixtus promoted the Franciscan belief in Immaculate Conception (belief that God rather than man fathered Jesus and that the Virgin Mary remained a virgin), which was opposed by the Benedictine Order and not accepted as Church dogma until 1854. 


Extending Franciscan feasts to whole Church. In wishing to increase the importance of the Virgin Mary and emphasize her virginity, the pope extended several feasts celebrated by the Franciscans to the whole Church:

Feast of the Presentation, 1472

Feast of the Visitation, 1475

Feast of the Immaculate Conception, 1476


Extending privileges of mendicant orders. Pope Sixtus also extended the privileges granted to the Franciscans and other mendicant orders such as the Benedictines.  Mendicant orders do not own property and are supported by their own work or by charity.  


Financial Crisis

In financing the 1472 Crusade and bestowing so many generous endowments on his family and friends, Pope Sixtus ran up a large deficit.  The situation was made worse by the executions of Pazzi-conspiracy plotters from the Pazzi and Salviati families, which had been the pope's bankers.


Annulment of Council of Constance

In 1478, Pope Sixtus annulled the provisions of the Council of Constance, which asserted the pre-eminence of an all-church council over the authority of the pope.  The Council of Constance had originally met in 1414-17, during the time of Martin V.


Not Reconvening Reform Council

The reputation and prestige of the papacy were gravely affected by Pope Sixtus' failure to manage the Church finances, to appoint qualified individuals to positions of responsibility, or to promote and maintain diplomatic relationships with other governing bodies.


To stop these abuses, the Croatian Archbishop, Andrea Zamometic, called for reconvening the Council of Basel, a council that had met between 1431-49 to make recommendations on reforming the Church.






Although little good can be said about Pope Sixtus' ethics or political judgment, his patronage of the arts resulted in several cultural institutions that remain today.


Enlarging Library's Space and Collection

Pope Sixtus is considered a second founder of the Vatican Library.  He moved it from an older part of the Vatican Palace to a larger suite on the ground story of the Nicholas V wing.  He also commissioned its decoration, which included frescoes by Melozzo da Forli.  He added almost a thousand more volumes to its collection of manuscripts, and he founded an Archive of Church documents.  In 1475, the pope created the post of chief librarian and appointed Bartolomeo Platina, who his papal predecessor, Paul II, had relieved of papal duties in an effort to purge pagan influence from Classical studies.  The Vatican collection was made available to visiting scholars as well as to local Church scholars.


Founding of the Sistine Choir

The pope, who did much to improve the Church music of his time, founded the Cappella Sistina (Sistine Choir), which has continued to this day as an important musical institution.


Establishing Roman Academy

The Royal Academy, which had been abolished by Paul II, was re-established.  This institution had been founded in 1460 under the humanist Pomponio Leto during the pontificate of Pius II and was devoted to the study of the culture of ancient Rome.





Urban-Renewal Projects

Sixtus embarked on a program of urban renewal for the city of Rome.


Streets. Many medieval Roman streets were widened and paved with brick.  These projects included the construction of the Borgo S. Angelo, which connected the Castel Sant' Angelo and the papal palace.  This street was originally named after Sixtus.  


Piazzas. The pope expanded many of the city's piazzas.  


Aqueduct:  Acqua Vergine. The pope had the Acqua Vergine aqueduct repaired and put into service.


Bridge:  Ponte Sisto. The pope built the Ponte Sisto (1473), which provided another link between the Vatican and the city center.


New Churches

Pope Sixtus founded two new churches in Rome.


Santa Maria del Popolo, Rome, begun 1472. The new church of Santa Maria del Popolo included a series of vaults on each side of the side aisles that were suitable for individual family chapels.  Many of them were sponsored by members of the della Rovere family and/or cardinals that Sixtus appointed.  


Santa Maria della Pace, Rome, 1478-83. Santa Maria della Pace's design was unusual in fusing a large rotunda with a nave and in having individual chapels instead of side aisles on each side of the nave.


Repairs to Older Buildings

Sixtus directed the repair and remodeling of many churches and hospitals in Rome.


Ospedale Santo Spirito. Sixtus rebuilt and expanded the charity hospital of Santo Spirito, which had been built at the end of the twelfth century.  Fresco scenes from the saint's life decorated part of the interior.  





Sistine Chapel, 1473-81. At the Vatican, Pope Sixtus built the Sistine Chapel, which is named for him.  Sixtus made Giovannino de' Dolci his head architect.  


Fresco scenes, Sistine Chapel, 1481-83. Between 1481 and 1483, Sixtus commissioned the leading painters from various parts of Italy to paint fresco scenes depicting the lives of Jesus Christ and Moses on opposite sides of the great hall.  While drawn together for this project, these painters formed a guild that marks the beginning of the Academy of St. Luke.  


Marble screen, Sistine Chapel. The pope also commissioned the carving of a marble screen that stood at one end.


Frescoes by Melozzo da Forli, Vatican Library. The pope commissioned Melozzo da Forli to paint the fresco decoration for the new library he established in the Nicholas V wing of the Vatican Palace.  Unfortunately, much of the decoration was destroyed later when the space was used for other purposes after the library collection was moved to a new wing that was built across the Belvedere Court in 1585.  The painting of Pope Sixtus appointing the library's first prefect while four of his nephews look on was transferred to canvas and moved to the Vatican art collection in the nineteenth century.


Bronze Tomb by Pollaiuolo of Sixtus IV, St. Peter's. After Sixtus' death, his nephew Giuliano commissioned Pollaiuolo to make a bronze tomb, which is considered to be one of that artist's finest works.













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