individual or body of people to whom the pope must manifest his renunciation. This addresses a concern raised in earlier centuries, specifically by 18th-century canonist Lucius Ferraris, who held that the College of Cardinals or at least its Dean must be informed, since the cardinals must be absolutely certain that the pope has renounced the dignity before they can validly proceed to elect a successor. In 1996, Pope John Paul II, in his Apostolic Constitution Universi Dominici gregis, anticipated the possibility of resignation when he specified that the procedures he set out in that document should be observed "even if the vacancy of the Apostolic See should occur as a result of the resignation of the Supreme Pontiff". History The Catholic Encyclopedia notes the historically obscure renunciations of Pontian (230–235) and Marcellinus (296–308), the historically postulated renunciation of Liberius (352–366), and mentions that one (unspecified) catalogue of popes lists John XVIII as resigning office in 1009 and finishing his life as a monk. 11th century The first historically unquestionable papal renunciation is that of Benedict IX in 1045. Benedict had also previously been deposed by Sylvester III in 1044, and though he returned to take up the office again the next year, the Vatican considers Sylvester III to have been a legitimate pope in the intervening months (meaning that Benedict IX must be considered to have validly resigned by acquiescing to the deposition in 1044). Then, in 1045, having regained the papacy for a few months, in order to rid the church of the scandalous Benedict, Gregory VI gave Benedict "valuable possessions" to resign the papacy in his favour. Gregory himself resigned in 1046 because the arrangement he had entered into with Benedict could have been considered simony. Gregory was followed by Clement II, and when Clement died, Benedict IX returned to be elected to the papacy for a third time, only to resign yet again before dying in a monastery. He thus reigned as pope for three non-consecutive terms, and resigned (or was deposed) three separate times. Celestine V A well-known renunciation of a pope is that of Celestine V, in 1294. After only five months as pope, he issued a solemn decree declaring it permissible for a pope to resign, and then did so himself. He lived two more years as a hermit and then prisoner of his successor Boniface VIII, and was later canonised. Celestine's decree, and