Pentarchy

Pentarchy (from Ancient Greek Πενταρχία (Pentarchía), from πέντε (pénte) 'five' and ἄρχειν (archein) 'to rule') was a model of Church organization formulated in the laws of Emperor Justinian I (r. 527–565) of the Roman Empire. In this model, the Christian Church is governed by the heads (patriarchs) of the five major episcopal sees of the Roman Empire: Rome, Constantinople, Alexandria, Antioch and Jerusalem.

The idea came about because of the political and ecclesiastical prominence of these five sees, but the concept of their universal and exclusive authority was attached to earlier Hellenistic-Christian ideas of administration. The pentarchy was first legally expressed in the legislation of Emperor Justinian I, particularly in Novella 131. The Quinisext Council of 692 gave it formal recognition and ranked the sees in order of preeminence, but its organization remained dependent on the emperor, as when Leo the Isaurian altered the boundary of patriarchal jurisdiction between Rome and Constantinople. Especially following Quinisext, the pentarchy was at least philosophically accepted in Eastern Orthodoxy, but in the West, the Rome based patriarchy evolved into the Roman Catholic Church, which would reject the Council as well as the concept of the pentarchy, considering itself the supreme church with universal jurisdiction.

The greater authority of these sees in relation to others was tied to their political and ecclesiastical prominence; all were located in important cities and regions of the Roman Empire and were important centers of the Christian Church. Rome, Alexandria and Antioch were prominent from the time of early Christianity, while Constantinople came to the fore upon becoming the imperial residence in the 4th century. Thereafter, it was consistently ranked just after Rome. Jerusalem received a ceremonial place due to the city's importance in the early days of Christianity.