Great Schism, or Schism of the West, division in the Roman Catholic Church from 1378 to 1417. There was no question of faith or practice involved; the schism was a matter of persons and politics. Shortly after Gregory XI had returned the papacy from Avignon to Rome, he died (Mar. 27, 1378). The Romans feared that the papal court might be returned to Avignon, and there was rioting, with the mob demanding a Roman, or at least an Italian, pope. On Apr. 8 the 16 cardinals present elected Urban VI. The new pope was soon acting very offensively to all in the church. The cardinals met at Agnani and on Aug. 2 declared Urban's election null. At Fondi on Sept. 20 they elected Robert of Geneva pope as Clement VII. Urban VI remained in Rome, refusing to step down, and Clement VII fled to Avignon, where he reigned surrounded by the former Roman court. There were thus two lines of popes. The popes at Rome were Urban VI (1378–89), Boniface IX (1389–1404), Innocent VII (1404–6), and Gregory XII (1406–15). Those of the rival line at Avignon were Clement VII (1378–94) and Benedict XIII (1394–1417; see Luna, Pedro de). Schism within schism ensued. France withdrew from obedience to Benedict XIII and recognized no pope (1398–1403, 1408–9). Theologians of the Univ. of Paris, led by Pierre d'Ailly and John Gerson, were anxious to end the schism, and they developed the theory that popes are subject to general councils. The Council of Pisa (1409; see Pisa, Council of) was the result. This meeting declared that Gregory XII of the Roman (or Urbanist) line and Benedict XIII of the Avignon (or Clementine) line were not popes and elected another, Alexander V. He died soon after, but his energetic successor, Baldassare Cossa (John XXIII, 1410–15), detached most of Europe from his rivals. In 1414 John reluctantly convened the Council of Constance (see Constance, Council of). Gregory XII resigned. John XXIII and Benedict XIII, who refused to resign, were declared deposed by the council. Martin V was elected, and the schism was at an end. The main effects of the schism were to delay needed reforms in the church and to give rise to the conciliar theory, which was revived at the Council of Basel (see Basel, Council of). It is generally agreed by Roman Catholic scholars that the line of popes from Urban to Gregory was the canonical one.
See W. Ullmann, Origins of the Great Schism (1948, repr. 1972); B. Tierney, Foundations of the Conciliar Theory (1955, repr. 1969); E. F. Jacob, Essays in the Conciliar Epoch (3d ed. 1963); M. Gail, The Three Popes (1969); J. H. Smith, The Great Schism (1970).