Pietro was born to the powerful Roman family of the Pierleoni, the son of the consul Pier Leoni. One of his great-great grandparents, Benedictus, maybe Baruch in Hebrew, was a Jew who converted into Christianity.2 As a second son with ambitions, Pietro was destined for an ecclesiastical career. He studied in Paris and entered the Benedictine Abbey of Cluny. Later he went to Rome and occupied several important positions.
In 1130, Pope Honorius II lay dying and the cardinals decided that they would entrust the election to a commission of eight men, led by papal chancellor Haimeric, who had his candidate Cardinal Gregory Papareschi hastily elected as Pope Innocent II. He was consecrated on February 14, the day after Honorius' death.
On the same day, the other cardinals, led by the senior Cardinal Bishop, Pietro of Porto, met with the leaders of Rome in the Basilica of S. Marco, and announced that Innocent had not been canonically elected. He nominated Cardinal Pietro Pierleoni, a Roman whose family were the enemy of Haimeric's supporters the Frangipani, who was elected by the Cardinals, clergy, nobility and People of Rome. Anacletus' supporters included the entire Roman aristocracy, with the exception of the Frangipani, and the majority of the Cardinals. With the support of the People, and in opposition to the French Haimeric, the Pierleoni were powerful enough to take control of Rome, while Innocent was forced to flee north of the Alps.
North of the Alps, Innocent gained the crucial support of St. Bernard of Clairvaux, Peter the Venerable, and other prominent reformers who helped him gain recognition from European rulers such as Emperor Lothair III, leaving Anacletus with few patrons. Anacletus had been a relatively acceptable candidate for the Papacy, being well-respected, so rumors centering on his descent from a Jewish convert were spread to blacken his reputation. Bernard of Clairvaux wrote: "It is a disgrace for Christ that a Jew sits on the throne of St. Peter's."3 Among his supporters were duke William X of Aquitaine, who decided for him against the will of his own bishops, and the powerful Roger II of Sicily, whose title of "King of Sicily" Anacletus had approved by papal bull after his accession.4
By 1135 Anacletus' position was weak despite their aid, but the schism only ended with his death in 1138, after which Gregorio Conti was elected as Victor IV but submitted to Innocent within a month. Innocent returned to Rome and ruled without opposition, quickly convening the Second Lateran Council in 1139 and reinforcing the Church's teachings against Usury, clerical marriage, and other practices.
Though the Pierleoni family mostly submitted to Innocent and his successors, Anacletus' brother Giordano, who was then leader of the Commune of Rome, actively opposed these successors in the following decade.
George L. Williams, Papal Genealogy: The Families and Descendants of the Popes, (McFarland & Company, Inc., 1998), p. 24 ↩
"Pierleóni nell'Enciclopedia Treccani". http://www.treccani.it/enciclopedia/pierleoni/ ↩
Fryde 2002, p. 103. - Fryde, Natalie (2002). "Abelard and the Church's Policy towards the Jews". In Gillingham, John (ed.). Anglo-Norman Studies XXIV: Proceedings of the Battle Conference 2001. The Boydell Press. pp. 99–108. ↩
Marjorie Chibnall, The Normans, (Wiley & Sons, 2006), 86. ↩