"In the history of Christianity, \"Pentarchy\" (from the Greek \u03A0\u03B5\u03BD\u03C4\u03B1\u03C1\u03C7\u03AF\u03B1, Pentarchia from \u03C0\u03AD\u03BD\u03C4\u03B5 pente, \"five\", and \u1F04\u03C1\u03C7\u03C9 archo, \"to rule\") is a proposed organisational structure where Christendom is ruled by the heads (or Patriarchs) of the five major episcopal sees of the Roman Empire: Rome, Constantinople, Alexandria, Antioch, and Jerusalem."@en . . .