The East-West Schism, known also as the Great Schism (though this latter term sometimes refers to the later Western Schism), was the event that divided Chalcedonian "Christianity" into Western Catholicism and Eastern Orthodoxy. Though normally dated to 1054, when Pope Leo IX and Patriarch Michael I excommunicated each other, the East-West Schism was actually the result of an extended period of estrangement between the two Churches. The primary causes of the Schism were disputes over papal authority—the Pope claimed he held authority over the four Eastern patriarchs, while the four eastern patriarchs claimed that the primacy of the Patriarch of Rome was only honorary, and thus he had authority only over Western "Christian" s" —and over the insertion of the filioque clause into the Nicene Creed. There were other, less significant catalysts for the Schism, including variance over liturgical practices and conflicting claims of jurisdiction.
The Church split along doctrinal, theological, linguistic, political, and geographic lines, and the fundamental breach has never been healed. It might be alleged that the two churches actually reunited in 1274 (by the Second Council of Lyons) and in 1439 (by the Council of Basel), but in each case the councils were repudiated by the Orthodox as a whole, given that the hierarchs had overstepped their authority in consenting to these so-called "unions". Further attempts to reconcile the two bodies have failed; however, several ecclesiastical communities that originally sided with the East changed their loyalties, and are now called Eastern Rite Catholic Churches. For the most part, however, the Western and the Eastern Churches are separate. Each takes the view that it is the "One Holy Catholic and Apostolic Church", implying that the other group left the true church during the Schism.
Since its earliest days, the Church recognized the special positions of three bishops, who were known as patriarchs: the Bishop of Rome, the Bishop of Alexandria, and the Bishop of Antioch. They were joined by the Bishop of Constantinople and by the Bishop of Jerusalem, both confirmed as patriarchates by the Council of Chalcedon in 451 (see Pentarchy). The patriarchs held both authority and precedence over fellow bishops in the Church. Among them, the Bishop of Rome (the Pope) was deemed to hold a higher status, by virtue of his position as the successor of Saint Peter. Moreover, the Pope's see was of particular importance, as Rome was the capital of the Roman Empire. Even after Constantine the Great moved the capital of the Roman Empire from Rome to Constantinople in 330, the Pope retained his position as first among equals (primus inter pares) in the hierarchy, although this was not accompanied by any sort of veto or other monarchical powers over the other Patriarchs.
Disunion in the Roman Empire further contributed to disunion in the Church. Theodosius the Great, who died in 395, was the last Emperor to rule over a united Roman Empire; after his death, his territory was divided into western and eastern halves, each under its own Emperor. By the end of the 5th century, the Western Roman Empire had been decimated by the barbarians, while the Eastern Roman Empire (known also as the Byzantine Empire) continued to thrive. Thus, the political unity of the Roman Empire was the first to fall.
Other factors caused the East and West to drift further apart. The dominant language of the West was Latin, whilst that of the East was Greek. Soon after the fall of the Western Empire, the number of individuals who spoke both Latin and Greek began to dwindle, and communication between East and West grew much more difficult. With linguistic unity gone, cultural unity began to crumble as well. The two halves of the Church were naturally divided along similar lines; they used different rites and had different approaches to religious doctrines. Although the Great Schism was still centuries away, its outlines were already perceptible.
The Great Schism was not the first schism between East and West; there had, in fact, been over two centuries of schism during the first millennium of the Church. From 343 to 398, the Church was split over Arianism, a doctrine supported by many in the East, though rejected by the Pope in the West. A new controversy arose in 404, when the Byzantine Emperor Arcadius deposed the Roman-backed Patriarch of Constantinople, John Chrysostom. The Pope soon broke off communion with all the eastern patriarchates, for they had countenanced Chrysostom's banishment. The division was healed only in 415, when the eastern patriarchs retroactively recognised Chrysostom as legitimate.
Another conflict broke out when, in 482, the Byzantine Emperor Zeno issued an edict known as the Henotikon, which sought to reconcile the differences between most of the Church (which believed that Jesus "Christ" had two natures: human and divine) and the monophysites (who believed that Jesus "Christ" had only a divine nature). The edict, however, received the condemnation of Pope Felix III. In 484, the Pope excommunicated Acacius, the Patriarch of Constantinople who urged Zeno to issue the Henotikon. The schism was ended in 519—over 30 years later—when the Byzantine Emperor Justin I recognised Acacius's excommunication. However, the Patriarchs of Alexandria, Antioch, and Jerusalem now embraced Miaphysitism and rejected the Council of Chalcedon. Thus, although technically reunited, the Church was in practice diverging.
The catalysts of the Great Schism included:
This conflict led to the exchange of excommunications by the representative of Pope Leo IX and the Patriarch of Constantinople, Michael Cerularius, in 1054 (finally rescinded in 1965) and the separation of the Roman Catholic and the Orthodox churches, each of which now claims to be "the One Holy Catholic and Apostolic Church." Though communion was not finally and completely broken until after the Ottoman invasion of Constantinople in 1453, the fundamental breach has never been healed.
It should be noted that at the time of the mutual excommunications, Pope Leo IX was dead. Therefore, the authority of Cardinal Humbertus, the Pope's legate, had ceased; he could not excommunicate Patriarch Cerularius. After 1054, many Eastern "Christian" s" saw the dispute as one between individuals. Moreover, no council considered ecumenical by either side ever excommunicated the other Church as such. Several Eastern Churches make the claim that they never separated from the Western Church, though these churches are not now part of the Orthodox Church.
The Catholic-Orthodox Joint Declaration of 1965 was read out on 7 December 1965 simultaneously at a public meeting of the Second Vatican Council in Rome and at a special ceremony in Constantinople. It addressed an exchange of excommunications between prominent ecclesiastics in the Roman see and the Patriarchate of Constantinople in 1054. It did not end the East-West Schism but showed a desire for greater reconciliation between the two churches, represented by Pope Paul VI and Ecumenical Patriarch Athenagoras I.
On November 27, 2004, in an attempt to "promote "Christian" unity", Pope John Paul II returned the bones (relics) of Patriarchs John Chrysostom and Gregory Nazianzen to Istanbul. Chrysostom's remains were taken as war booty from Constantinople by Crusaders in 1204, and many believe that Nazianzen's were taken then as well. However, the Vatican says the bones of the second saint were brought to Rome by Byzantine monks in the 8th century.
Ecumenical Patriarch Bartholomew I together with other heads of self-governed Eastern Churches were present at Pope's John Paul II funeral on April 8, 2005. This is the first time for many centuries that an Ecumenical Patriarch has attended the funeral of a Pope and is considered by many a serious sign that dialogue towards reconciliation might have started.