East–West Schism

The East–West Schism, often called the Great Schism, is the division between the Catholic Church in the West and the Eastern Orthodox Church. It is conventionally dated to 1054, when papal legates and the patriarch of Constantinople excommunicated each other, but it was the outcome of centuries of drifting apart and only hardened into a lasting break over the following two centuries. The two churches remain separate today.

After the Roman Empire divided, the Latin-speaking West and the Greek-speaking East developed different languages, liturgies, customs and ideas of church government. Rome and Constantinople were two of the five great sees of the early church, known as the pentarchy. The popes increasingly claimed authority over the whole church, while the eastern churches saw the bishop of Rome as first in honour among patriarchs rather than as a ruler over them. Political changes widened the gap: the coronation of Charlemagne as emperor in 800 created a western empire that the Byzantines regarded as a rival to their own.

The most famous theological disagreement concerned the Filioque, a phrase added in the West to the Nicene Creed stating that the Holy Spirit proceeds from the Father "and the Son". Eastern theologians objected both to the doctrine and to the fact that the creed had been altered without an ecumenical council. Other disputes concerned the use of unleavened bread in the Eucharist, clerical celibacy and rival missionary efforts among the Slavs and Bulgarians. In the 860s a quarrel between Pope Nicholas I and Patriarch Photius led to a temporary break.

In 1053 Patriarch Michael Cerularius closed the Latin churches in Constantinople, partly in response to Norman and papal pressure on Greek churches in southern Italy. Pope Leo IX sent a delegation led by Cardinal Humbert of Silva Candida to the capital. The talks went badly, and on 16 July 1054 Humbert laid a bull of excommunication against Cerularius on the altar of Hagia Sophia. The patriarch and his synod replied by excommunicating the legates. Leo IX had in fact died in April, so the legates' authority was doubtful, and the excommunications were personal rather than directed at whole churches. At the time few people saw the episode as final.

Relations worsened in the following centuries. The Crusades brought western armies into the eastern Mediterranean, and Latin bishops replaced Greek ones in conquered cities. The decisive blow came in 1204, when the Fourth Crusade sacked Constantinople and set up a Latin empire and a Latin patriarch there, leaving deep bitterness among Orthodox Christians. Attempts at reunion were made at the Councils of Lyon in 1274 and Florence in 1439, but in both cases the union was rejected by most of the clergy and people in the East. After the fall of Constantinople in 1453, the Ottoman authorities recognised the Orthodox patriarch as head of their Orthodox subjects, and the agreement of Florence lapsed.

In the twentieth century the churches began to talk again. In 1964 Pope Paul VI and Ecumenical Patriarch Athenagoras met in Jerusalem, and on 7 December 1965 they jointly lifted the excommunications of 1054. In 2001 and 2004 Pope John Paul II expressed regret for the sack of Constantinople. Theological dialogue continues, but questions of papal authority remain the main obstacle to full communion.

Our 1000 and 1100 maps show the Byzantine Empire, heartland of the Orthodox church, alongside the Holy Roman Empire and the Papal States in the Latin West.