Western Schism

A division in the Catholic Church from 1378 to 1417, when rival popes claimed authority from Rome and Avignon, and later Pisa. It ended when the Council of Constance elected Martin V.

Pope Gregory XI: The pope who returned the papal court from Avignon to Rome in 1377. His death in Rome in 1378 left the papacy’s succession contested.
Papal conclave: The meeting of cardinals that elects a pope. Disagreement over the validity of the 1378 conclave drove the first rival papal claims.
Pope Benedict XIII: The Avignon claimant who held the papacy from 1394 until his death in 1423, despite being deposed by Constance. His refusal to resign obstructed the council’s effort to restore unity.
Council of Constance: A church council held from 1414 to 1418 that ended the Western Schism and elected Martin V. Its elections and depositions brought the rival papal claims to an end.
Pope Urban VI: The pope elected in Rome in 1378 whose election was rejected by rival cardinals. His election created the Roman line of claimants.
Papal legitimacy: The recognized right of a pope to hold the office and exercise its authority. Each obedience treated its own claimant as the legitimate pope.
Pope Gregory XII: The Roman claimant from 1406 who resigned in 1415 during the Council of Constance. His resignation helped clear the way for a new papal election.
Haec sancta: A decree of the Council of Constance in 1415 asserting the authority of a general council in matters of church reform and unity. The decree expressed the council’s claim to authority amid divided papal leadership.
Pope Clement VII: The antipope elected at Fondi in 1378 who established a rival court in Avignon. His election established the Avignon line against Urban VI.
Obedience (papacy): A political and ecclesiastical bloc recognizing one claimant to the papacy. European rulers and churches divided into rival obediences.

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