The Great Schism of 1054 was a watershed episode in Christian history, and its consequences changed Europe’s religious composition for decades. A schism is a division caused by differing beliefs, and the Great Schism divided the Christian Church along East-West lines.
The official separation of the Western Catholic and Eastern Orthodox churches was definitely a key impact of the schism. As demonstrated during the Fourth Crusade and the Sack of Constantinople in 1204, the split increased hostilities between Western and Eastern Christians.
Michael Cerularius, Patriarch of Constantinople, was excommunicated from the Christian church established in Rome, Italy, on July 16, 1054. The excommunication of Cerularius was a watershed moment in the long-rising tensions between the Roman church in Rome and the Byzantine church in Constantinople (now called Istanbul).
As a consequence, the European Christian church was divided into two main branches: the Western Roman Catholic Church and the Eastern Orthodox Church. The Great Schism, also known as the “East-West Schism” or the “Schism of 1054,” is the name given to this divide.
The Great Schism arose from a complicated combination of theological and political tensions. One of the major theological differences between the western (Roman) and eastern (Byzantine) branches of the church was whether or not unleavened bread may be used for the sacrament of communion.
(The west favored the practice, while the east opposed it.) Other points of contention in religion include the precise language of the Nicene Creed and the Western assumption that priests should be celibate.
A number of political problems, notably those involving Rome’s influence, exacerbated these theological divisions. Rome felt that the pope, as the western church’s religious head, should have jurisdiction over the patriarch, as the eastern church’s religious leader.
Constantinople was not convinced. When the western church ultimately excommunicated Michael Cerularius and the whole eastern church. The eastern church replied by excommunicating both the Roman pope, Leo III, and the Roman church as a whole.
While the two churches never rejoined, the western and eastern branches of Christianity came to more peaceful terms over a thousand years following their separation. Pope Paul VI and Patriarch Athenagoras I removed their respective churches’ long-standing mutual excommunication decrees in 1965.
Today, the two branches of Christianity continue to be separate expressions of the same religion. With over a billion adherents worldwide, Roman Catholicism is the biggest Christian denomination. With over 260 million adherents, Eastern Orthodoxy is the second-largest Christian church. National churches within Eastern Orthodoxy include the Greek Orthodox Church and the Russian Orthodox Church.
Christianity’s spread. The Great Schism divided Christianity’s major factions into two camps: Roman Catholic and Eastern Orthodox. They are still the two major Christian groups today.
How did the Great Schism (1378–1417) contribute to the end of the Western European Middle Ages? It significantly undermined the Roman Catholic Church’s influence and reputation. It prevented the Papacy from being relocated from Rome to Avignon, France. The Black Death killed about one-third of Western Europe’s population.
In 1417, the Council elected Pope Martin V, thereby resolving the schism. The Crown of Aragon refused to acknowledge Pope Martin V and instead continued to recognize Pope Benedict XII.
Western Schism, also known as Great Schism or Great Western Schism, was a time in the history of the Roman Catholic Church from 1378 to 1417 when there were two, and subsequently three, competing popes, each with his own followers, Sacred College of Cardinals, and administrative positions.
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