to resign of his own accord was Gregory XII in 1415 (to help end the Western Schism), followed by Benedict XVI in 2013, 719 years later. Retirement, death, and canonization The former Celestine, now reverted to Pietro Angelerio, was not allowed to become a hermit once again. Various parties had opposed his resignation and the new Pope Boniface VIII had reason to worry that one of them might install him as an antipope. To prevent this he ordered Pietro to accompany him to Rome. Pietro escaped and hid in the woods before attempting to return to Sulmona to resume monastic life. This proved impossible, and Pietro was captured after an attempt to flee to Dalmatia was thwarted when a tempest forced his ship to return to port. Boniface imprisoned him in the castle of Fumone near Ferentino in Lazio, attended by two monks of his order, where Pietro died after 10 months at about the age of 81. His supporters spread the allegation that Boniface had treated him harshly and ultimately executed Pietro, but there is no clear historical evidence of this. Pietro was buried at Ferentino, but his body was subsequently moved to the Basilica of Santa Maria di Collemaggio in L'Aquila. Philip IV of France, who had supported Celestine and bitterly opposed Boniface, nominated Celestine for sainthood following the election of Pope Clement V. The latter signed a decree of dispensation on 13 May 1306 to investigate the nomination. He was canonized on 5 May 1313 after a consistory in which Boniface's Caetani family was outvoted by members of the rival Colonna family. Legacy Most modern interest in Celestine V has focused on his resignation. He was the first pope to formalize the resignation process and is often said to have been the first to resign; in fact he was preceded in this by Pontian (235), John XVIII (1009), Benedict IX (1045), and Gregory VI (1046). As noted above, Celestine's own decision was brought about by mild pressure from the Church establishment. His reinstitution of Gregory X's conclave system established by the papal bull Ubi periculum has been respected ever since. A 1966 visit by Pope Paul VI to Celestine's place of death in Ferentino along with his speech in homage of Celestine prompted speculation that the Pontiff was considering retirement. Celestine's remains survived the 2009 L'Aquila earthquake with one Italian spokesman saying it was "another great miracle