<P> After the Roman Emperor Constantine the Great legalized Christianity (with the Edict of Milan), he summoned the First Ecumenical Council at Nicaea in 325 . The bishops at the council confirmed the position of the metropolitan sees of Rome and Alexandria as having authority outside their own province, and also the existing privileges of the churches in Antioch and the other provinces . These sees were later called Patriarchates . These were given an order of precedence: Rome, as capital of the empire was naturally given first place, then came Alexandria and Antioch . In a separate canon the Council also approved the special honor given to Jerusalem over other sees subject to the same metropolitan . </P> <P> Roman dominate Emperor Theodosius I convened the second ecumenical council (Constantinople I) at the imperial capital city in 381 . The council elevated the see of Constantinople, to a position ahead of the other chief metropolitan sees, except that of Rome thus raising it above the sees of Alexandria and Antioch . This action has been described as sowing the seed for the ecclesiastical rivalry between Constantinople and Rome which was ultimately a factor leading to the schism between East and West . It demarcated the territory within the praetorian prefecture of the East into five canonical territories corresponding to the five civil dioceses: Diocese of Egypt (metropolis in Alexandria), Diocese of the East (metropolis in Antioch), Diocese of Asia (Metropolis of Ephesus), Diocese of Pontus (metropolis in Caesarea Cappadociae), and Diocese of Thrace (metropolis in Heraclea, later under Constantinople); The council mentioned the churches in the civil dioceses of Asia, Pontus, and Thrace, it decreed that the synod of each province should manage the ecclesiastical affairs of that province alone, except for the privileges already recognized for sees of Alexandria and Antioch . </P> <P> No Western bishops attended the council and no legate of the bishop of Rome was present . The Latin Church recognized the council as ecumenical about 150 years later, in the mid-6th century . </P> <P> Rome's Tome of Leo (449) was highly regarded, and formed the basis for the Council of Chalcedon formulation . But it was not universally accepted and was even called "impious" and "blasphemous" by those who condemned the council that approved and accepted it . The next ecumenical council corrected a possible imbalance in Pope Leo's presentation . Although the Bishop of Rome was well respected even at this early date, the East holds that the concept of the primacy of the Roman See and Papal Infallibility were only developed much later . </P>

Schism of roman catholic and eastern orthodox religions