Pope Gregory XII (; ; – 18 October 1417), born Angelo Corraro, Corario, or Correr, was head of the Catholic Church from 30 November 1406 to 4 July 1415. Reigning during the Western Schism, he was opposed by the Avignon claimant Benedict XIII and the Pisan claimants Alexander V and John XXIII. Gregory XII wanted to unify the Church and voluntarily resigned in 1415 to end the schism. Early life Angelo Corraro was born in Venice of a noble family, about 1327, and was appointed Bishop of Castello in 1380, succeeding Bishop Nicolò Morosini. On 1 December 1390 he was made titular Latin Patriarch of Constantinople. On 12 June 1405 he was created cardinal and the Cardinal-Priest of San Marco by Pope Innocent VII. He was Apostolic Administrator of Constantinople from 30 November 1406 to 23 October 1409. Pontificate Gregory XII was chosen at Rome on 30 November 1406 by a conclave consisting of only fifteen cardinals under the express condition that, should Antipope Benedict XIII (1394–1423), the rival papal claimant at Avignon, renounce all claim to the papacy, he would also renounce his, so that a fresh election might be made and the Western Schism (1378–1417) ended. Negotiations to end the schism The two claimants opened wary negotiations to meet on neutral turf at Savona in Liguria, but soon began to waver in their resolve. The Corraro relatives of Gregory XII in Venice and King Ladislaus of Naples, a supporter of Gregory XII and his predecessor for political reasons, used all their influence to prevent the meeting, and each claimant of the papal title feared being captured by partisans of his rival. The cardinals of Gregory XII openly showed their dissatisfaction at this manoeuvring and gave signs of their intention to abandon him. On 4 May 1408, Gregory XII convened his cardinals at Lucca and ordered them not to leave the city under any pretext. He tried to supplement his following by creating four of his Corraro nephews cardinals – including the future Pope Eugene IV, despite his promise in the conclave that he would create no new cardinals. Seven of the cardinals secretly left Lucca and negotiated with the cardinals of Benedict XIII concerning the convocation of a general council by them, at which both Gregory XII and Benedict XIII should be declared deposed and a new pope elected. Consequently, they convoked the Council of Pisa and invited