Conciliar Movement

Conciliarism was a reform movement in the 14th-, 15th- and 16th-century Catholic Church which held that supreme authority in the Church resided with an Ecumenical council, apart from, or even against, the pope. The movement emerged in response to the Western Schism between rival popes in Rome and Avignon. The schism inspired the summoning of the Council of Pisa (1409), which failed to end the schism, and the Council of Constance (1414–1418), which succeeded and proclaimed its own superiority over the Pope. Conciliarism reached its apex with the Council of Basel (1431–1449), which ultimately fell apart. The eventual victor in the conflict was the institution of the Papacy, confirmed by the condemnation of conciliarism at the Fifth Lateran Council, 1512–17. The final gesture however, the doctrine of Papal Infallibility, was not promulgated until the First Vatican Council of 1870.

The 13th and 14th centuries were a period of challenges to Papal authority in Catholic Europe. These new challenges were marked by disputes between the Papacy and the secular kings of Europe. In particular the quarrel between Philip IV of France and Pope Boniface VIII over the right to tax the clergy in France was especially heated. Philip was excommunicated and Boniface was accused of corruption, sorcery, and sodomy. In his "Unam Sanctam", Boniface asserted that the papacy held power over both the spiritual and temporal worlds and that only God could judge the pope. Philip responded by sending knights to Italy to arrest Boniface. Though the mission eventually failed, the Pope died just three weeks after his release because of the trauma of the experience and a high fever.

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