Boniface concurring (not revoking it), ended any doubt among canonists about the possibility of a valid papal renunciation. Western Schism Gregory XII (1406–1415) resigned in 1415 in order to end the Western Schism, which had reached the point where there were three claimants to the papal throne: Roman Pope Gregory XII, Avignon Antipope Benedict XIII, and Pisan Antipope John XXIII. Before resigning, he formally convened the already existing Council of Constance and authorized it to elect his successor. Benedict XVI Benedict XVI's renunciation of the papacy took effect on 28 February 2013 at 20:00 (8:00 pm) CET (19:00 UTC), after being announced on the morning of 11 February by the Vatican. He was the first pope to relinquish the office since Gregory XII resigned to end the Western Schism in 1415 and the first to do so on his own initiative since Celestine V in 1294. His action was unexpected, given that the modern era popes have held the position from election until death. He said he was motivated by his declining health due to old age. The conclave to select his successor began on 12 March 2013 and elected Cardinal Jorge Mario Bergoglio, Archbishop of Buenos Aires, who took the name Francis. List of papal renunciations Conditional renunciations not put into effect Before setting out for Paris to crown Napoleon in 1804, Pope Pius VII (1800–1823) signed a document of renunciation to take effect if he were imprisoned in France. During World War II, Pope Pius XII drew up a document ordering that his resignation take effect immediately if he were kidnapped by the Nazis, as was thought likely in August 1943. It was thought that the College of Cardinals would evacuate to a neutral country, perhaps Portugal, and elect his successor. According to longtime curial official Cardinal Giovanni Battista Re, Pope Paul VI handwrote two letters in the late 1960s or 1970, well before his death, in anticipation of an incapacitating illness. One letter was addressed to the College of Cardinals, the other to the Secretary of State, whose name was not specified. Pope John Paul II showed them to Re, and they were shown to Pope Benedict XVI in 2003. In 2018, Paul's letter dated 2 May 1965 and addressed to the dean of the College of Cardinals was published. He wrote that "In case of infirmity, which is believed to be incurable or is of long