The Levantine Christian Churches are the oldest Christian Communions on earth. They include the Patriarchate of Jerusalem, which has existed in one form or another since the time of events described in the Book of Acts. As a distinct branch of Christianity, the East evolved away from the West as Constantinople and the Hellenic heirs to the Roman Empire distanced itself from Rome, the Latins, and their heirs. The final break is often said to have taken place in 1054 CE, when a Papal legate in Constantinople to discuss problems and issues, was moved to place a ban of excommunication upon the altar of Hagia Sophia Cathedral against the Patriarch of that city, but in truth, discord between east ands west predates the 11th century by quite awhile, and attempts at reconciliation have occured for centuries after. It is important to realize that each branch recognized the breach as a species of schism, not heresy - both recognize the validity of the priestly orders and apostolic succession of the other, and, in truth, aside from the somewhat technical theological dispute of the filioque clause in the Creed, the primary basis for continued dissent lies in the fact that the Eastern Patriarchates described below, and their associated national churches, will not recognize the authority of the Western Pope - and the Roman Patriarch will not abandon his claim to merit the full obedience of all Christian churches everywhere.
In a separate file, the Churches of: Albania, Bulgaria, Cyprus, Czech Lands and Slovakia, Georgia, Greece, Poland, Romania, Russia, Serbia, the Orthodox Church in America, and the Autonomous Churches in Finland, Japan, Sinai, Ukraine. Note as well, the emerging but as-yet unsanctioned Church of Macedonia, based at the ancient See of Ohrid.