Gregory XII, c.1327–1417, pope (1406–15), a Venetian named Angelo Correr; successor of Innocent VII. As a condition of election, Gregory promised to do everything possible to end the Great Schism, including the relinquishing of his office. Negotiations were opened with the Avignon antipope, Benedict XIII (see Luna, Pedro de), but soon broke down under pressure from Gregory's family. Seven of his cardinals thereupon defected and together with a group of Avignon cardinals convoked the Council of Pisa (see Pisa, Council of) which elected a second antipope, Alexander V. The Council of Constance (see Constance, Council of) deposed the two antipopes, accepted Gregory's resignation (1415), and saw to the proper election of Martin V (1417). Gregory died as cardinal bishop of Porto.