That's So Second Millennium

Changing the numbering system to be more suggestive of a bracket. Sixtus is the third one seed, if you will.

Image: Sandro Botticelli, 1480, Pope Sixtus II

Popes names Sixtus (originally Xystus):

St Sixtus I 117 or 119 to 126 or 128 Martyr

St Sixtus II 257 to 258 Famous martyr, in the Roman Canon

St Sixtus III 432 to 440

Sixtus IV 1471 to 1484 Sistine Chapel named for him

Sixtus V 1585 to 1590 Great reformer of the Papal States and Curia

 

Sixtus or Xystus I: the earliest pope we have covered so far, in the very uncertain period of the second century, during the reign of Hadrian. The chronicles that look back to this time do not agree on the dates of his ministry and otherwise only record a few vague details. He is supposed to have placed the chanting of the Sanctus at its present place in the Mass, right after the Preface; he is also recorded to have been martyred, although nothing seems to be preserved about the event.

 

Sixtus / Xystus II: pope during the persecution of Valerian in the third century. His brief reign saw a reconciliation with St. Cyprian and churches in Africa and Asia Minor, which had been requiring heretics to be rebaptized. The persecution was stepped up in August 258 and Pope Xystus was beheaded with four deacons in a cemetery where he was celebrating Mass; two more deacons were executed the same day; the last and most famous deacon, Lawrence, survived a few days to be captured and according to legend roasted to death. Pope Sixtus to this day is mentioned in the full version of the Roman Canon of the Eucharistic Prayer.

 

Sixtus / Xystus III: prior to his election as pope, a correspondent with St. Augustine. Approved the acts of the Council of Ephesus and rededicated the restored basilica of St. Mary Major. This historical period included continued disputes with both Pelagians and Nestorians. Defended and maintained papal supremacy over Illyricum. Succeeded by Leo the Great.

 

Sixtus IV: pope of the late fifteenth century. Born of poor parents; became a Franciscan and a notable theologian. Unfortunately once pope he became a traditional nepotist and involved the Papal States in wars to put his nephews in charge of Florence and Ferrara, and wars of this nature continued to absorb papal attention through the beginning of the Reformation. He opposed and annulled the decrees of the Council of Constance and was successful in turning the Church away from conciliarism. He was a great builder and is said to have made Rome much more livable, helping continue its recovery from the Avignon period of the papacy. He reorganized and essentially refounded the Vatican Library and most famously built the Sistine Chapel.

 

Sixtus V: also of poor birth and Dalmatian ancestry, whose family had fled from Turkish expansion; supposedly a swineherd as a boy. Also became a Franciscan and rose to prominence in that order, also for a time appointed to the Inquisition in Venice. Accompanied the future Gregory XIII to Spain to investigate claims that the Archbishop of Toledo was a heretic, and the two did not get along. During Gregory XIII's long reign he was sidelined. Similarly to his time as an inquisitor, he proved to be an effective but severe and even brutal ruler of the Papal States. He had perhaps ten thousand to thirty thousand brigands to deal with and nearly exterminated them. He put the papal finances in order and built many useful and beautiful buildings, but seems to have taxed the economy into a stupor. Of particular significance, he created fifteen Congregations to organize the cardinals and created much of the current structure of the Curia. He caused editions of the Septuagint and the Vulgate to be printed, although his edition of the Vulgate is not considered to be of high quality, and even at the time was recalled and corrected in 1592 due to many errors already recognized. He was supposedly on the point of forcing the Jesuits to change their name from the "Society of Jesus" and change some of the rules of the order when he died. For a change he was actually notably non-nepotistic.

 

Why Sixtus VI: A cardinal would take this name in order to revive the memory of Sixtus II (and I), recognizing that the Church in so many parts of the world faces persecution on a massive scale. That by itself might be enough. The early modern era Popes Sixtus, especially Sixtus V, might contribute to the idea especially if 1) the cardinal is a Franciscan and 2) he plans to address the Vatican finances and the organization of the Curia at large.