The [[First Ecumenical Council|First Council of Nicea]] singled out three great centers: [[Church of Rome|Rome]], [[Church of Alexandria|Alexandria]], and [[Church of Antioch|Antioch]] (Canon 6). It also laid down that the see of [[Church of Jerusalem|Jerusalem]], while remaining subject to the Metropolitan of Caesarea, should be given the next place in honor after these three (Canon 7). ([[Church of Constantinople|Constantinople]] naturally was not mentioned, since it was not officially inaugurated as the new capital until five years later; it continued to be subject, as before, to the Metropolitan of Heraclea.).

This system is now known among Orthodox as the [[Pentarchy]], whereby the five great sees of the Church were held in honor, and established a particular order of precedence among them: