* 1483 – Pope Sixtus IV consecrates the Sistine Chapel.

Pope Sixtus IV gave the nuns canonical status in 1474.

Pope Paul II suppressed this college ; but Sixtus IV ( Constitutio 16, " Divina ") reestablished it.

Abbreviators of the lower presidency before their suppression were simple clerics, and according to permission granted by Sixtus IV ( loc.

The church and monastery of San Pietro in Montorio originally belonged to the Celestines in Rome ; but they were turned out of it by Sixtus IV to make way for Franciscans, receiving from the Pope in exchange the Church of St Eusebius of Vercelli with the adjacent mansion for a monastery.

More likely, Pope Sixtus IV granted Cesare a release from the necessity of proving his birth in a papal bull of 1 October 1480.

Coming from modest beginnings in Savona, Liguria, the family rose to prominence through nepotism and ambitious marriages arranged by two Della Rovere popes, Francesco della Rovere, who ruled as Pope Sixtus IV ( 1471 – 1484 ) and his nephew Giuliano ( Pope Julius II, 1503 – 1513 ).

Pope Sixtus IV is known for having built the Sistine Chapel, which is named for him.

On 28 February 1476, Pope Sixtus IV, a Franciscan after whom the Sistine Chapel is named, authorized those dioceses that wished to introduce the feast to do so, and introduced it to his own diocese of Rome in 1477, with a specially composed Mass and Office of the feast.

In Rome, the papal collections were brought together by Pope Nicholas V, in separate Greek and Latin libraries, and housed by Pope Sixtus IV, who consigned the Bibliotheca Apostolica Vaticana to the care of his librarian, the humanist Bartolomeo Platina in February 1475.

* 1477 – Uppsala University is inaugurated after receiving its corporate rights from Pope Sixtus IV in February the same year.

The most important member of the Monterotondo Orsinis was Giovani Battista Orsini, who became cardinal under Sixtus IV ( 1483 ).

Bartolomeo Platina, the scholar who was prefect of the Vatican Library, wrote his Vitæ Pontificum Platinæ historici liber de vita Christi ac omnium pontificum qui hactenus ducenti fuere et XX in 1479 at the behest of his patron, Pope Sixtus IV.

Cardinal Piccolomini participated in the conclave that elected Pope Paul II ( 1464 – 71 ) in 1464, but was absent when Pope Sixtus IV ( 1471 – 84 ) was elected in 1471.

He was employed in several important legations, as by Paul II at the Imperial diet at Regensburg / Ratisbon, and later by Sixtus IV to restore ecclesiastical authority in Umbria.

This selection can be seen as a compromise between factions, Borgia and della Rovere, picking a frail cardinal with long experience in the Curia over the kin of either Sixtus IV or Alexander VI.

Instigated by the king of Spain and the duke of Mayenne, he excommunicated Henry IV of France on 1 March 1591, reiterating the 1585 declaration of Pope Sixtus V that as a heretic ( Protestent ) Henry of Navarre was ineligible to succeed to the throne of Catholic France and deprived of his dominions.

The influence of his friends procured for him, from Pope Paul II ( 1464 – 71 ), the bishopric of Savona, and in 1473, with the support of Giuliano Della Rovere, later Pope Julius II, he was made cardinal by Pope Sixtus IV, whom he succeeded on 29 August 1484 as Pope Innocent VIII.

Giuliano della Rovere was the son of Rafaello della Rovere nephew of Pope Sixtus IV and of Theodora Manerola, a lady of Greek extraction.

Giuliano was an altar boy of his uncle Pope Sixtus IV ( Francesco della Rovere ).

Giulliano della Rovere, as cardinal, age 34 ( left ) with uncle and patron Francesco della Rovere, Pope Sixtus IV ( right ).

His remains, along with those of his uncle, Pope Sixtus IV, were later desecrated during the Sack of Rome in 1527.

Pope Sixtus IV ( 21 July 1414 – 12 August 1484 ), born Francesco della Rovere, was Pope from 1471 to 1484.

Like a number of Popes, Sixtus IV adhered to the system of nepotism.

To this, Sixtus IV replied with an interdict and two years ' of war with Florence.

At the age of 27 he was appointed Bishop of Ross by Pope Sixtus IV.

When he returned to Munster he discovered that the see was already in the possession of Hugh O ' Driscoll, who had been appointed to the see in 1473 by the same Pope Sixtus.

After his accession as Sixtus V, he appointed Fontana architect of St. Peter's, bestowing upon him, among other distinctions, the title of Knight of the Golden Spur.

Nominated Protonotary Apostolic in 1481, he was appointed Master of Ceremonies to Pope Sixtus IV in 1483, having bought the office for 450 ducats.

Pope Sixtus III appointed Peter to the See of Ravenna in about the year 433, apparently rejecting the candidate elected by the people of the city.

* Sixtus of Tannberg ( appointed 12 January 1474 ; died 14 July 1495 )

Bulls in favour of the shrine at Loreto were issued by Pope Sixtus IV in 1491 and by Julius II in 1507, the last alluding to the translation of the house with some caution ( ut pie creditur et fama est ); While, like most miracles, the translation of the house is not a matter of faith for Catholics, nonetheless, in the late 17th century, Innocent XII appointed a missa cum officio proprio ( a special mass ) for the feast of the Translation of the Holy House, and as late as the 20th century, the feast was enjoined in the Spanish Breviary as a greater double ( December 10 ).

In the 16th century Sixtus V bisected Bramante's Cortile del Belvedere with a cross-wing to house the Apostolic Library in suitable magnificence. The 16th and 17th centuries saw other privately endowed libraries assembled in Rome: the Vallicelliana, formed from the books of Saint Filippo Neri, with other distinguished libraries such as that of Cesare Baronio, the Biblioteca Angelica founded by the Augustinian Angelo Rocca, which was the only truly public library in Counter-Reformation Rome ; the Biblioteca Alessandrina with which Pope Alexander VII endowed the University of Rome ; the Biblioteca Casanatense of the Cardinal Girolamo Casanate ; and finally the Biblioteca Corsiniana founded by the bibliophile Clement XII Corsini and his nephew Cardinal Neri Corsini, still housed in Palazzo Corsini in via della Lungara. The Republic of Venice patronized the foundation of the Biblioteca Marciana, based on the library of Cardinal Basilios Bessarion. In Milan Cardinal Federico Borromeo founded the Biblioteca Ambrosiana.

The secular fortunes of the Della Rovere began when Sixtus invested his nephew Giovanni with the lordship of Senigallia and arranged his marriage to the daughter of Federico III da Montefeltro, duke of Urbino ; from this union came a line of Della Rovere dukes of Urbino that lasted until the line expired in 1631.

In his territorial aggrandizement of the Papal States, Sixtus IV's niece's son Cardinal Raffaele Riario, for whom the Palazzo della Cancelleria was constructed, was a leader in the failed " Pazzi conspiracy " of 1478 to assassinate both Lorenzo de ' Medici and his brother Giuliano and replace them in Florence with Sixtus IV's other nephew, Girolamo Riario.

In 1475 pope Sixtus IV raised the diocese of Avignon to the rank of an archbishopric, in favour of his nephew Giuliano della Rovere, who later became Pope Julius II.

In his larger political relations, Sixtus entertained fantastic ambitions, such as the annihilation of the Turks, the conquest of Egypt, the transport of the Holy Sepulchre to Italy, and the accession of his nephew to the throne of France.

Lorenzo did manage to save the nephew of Sixtus IV, Cardinal Raffaele Riario, who was almost certainly an innocent dupe of the conspirators, as well as two relatives of the conspirators.

In 1474, Sixtus IV sent his nephew, Cardinal Giuliano della Rovere ( later Julius II ); after fruitless negotiations he laid siege to the city, but Vitelli did not surrender until he learned that the command of the army had been given to Duke Federico III da Montefeltro.

Following the death of Gambara in 1587, he was succeeded as Apostolic Administrator of Viterbo, by the 17-year-old nephew of Pope Sixtus V, Cardinal Alessandro Peretti di Montalto.

It was again brought under papal authority when it was bestowed as dowry on Catherine Sforza, the bride of Girolamo Riario, nephew of Pope Sixtus IV.

From 1471 to 1503, in which year he was elected Pope Julius II, Cardinal Della Rovere, the nephew of Pope Sixtus IV, effected notable rebuilding.

With the prior patron's death, direction of the church passed to Cardinal Alessandro Peretti di Montalto, nephew of Sixtus V. By 1608, and banked by the then enormous endowment of over 150 thousand gold scudi, work restarted anew with a more grandiose plan, mainly by Carlo Maderno.

Girolamo was given a leading position in the expansion policy of Pope Sixtus IV after the premature death of the Pope's favoured nephew, Cardinal Pietro Riario.

When he died aged 40, under suspicion of poisoning, the situation of Forlì was weakened as factions of Ordelaffi fought one another, until Pope Sixtus IV claimed the signory for his nephew Gerolamo Riario.

The king then appeals to the reigning Pope Julius II ( nephew of Sixtus IV ) to grant the aspirations of these new Christians.