Originally a patriarch was a man who exercised autocratic authority as a pater familias over an extended family. The system of such rule of families by senior males is called patriarchy. This is a Greek word, a composition of πατήρ (pater) meaning "father" and ἄρχων (archon) meaning "leader", "chief", "ruler", "king", etc.
The word has mainly taken on specific ecclesiastical meanings. In particular, the highest-ranking bishops in Eastern Orthodoxy, Oriental Orthodoxy, the Roman Catholic Church (above Major Archbishop and primate), and the Assyrian Church of the East are called patriarchs. The office and ecclesiastical conscription (comprising one or more provinces, though outside his own (arch)diocese he is often without enforceable jurisdiction) of such a patriarch is called a patriarchate. Historically, a Patriarch may often be the logical choice to act as Ethnarch, representing the community that is identified with his religious confession within a state or empire of a different creed (as Christians within the Ottoman Empire).
The four presbygenē ("senior-born", ancient) Patriarchates; before the Great Schism of 1054 these included the See of Rome as "first among equals", and were counted as five:
As part of the Pentarchy, the Pope's Patriarchate of Rome was the only one in the Western Roman empire. It was roughly coterminous with present territory of the Latin Rite. In the past popes have used the title Patriarch of the West. However, this title was removed from a reference publication issued by the Vatican in 2006.[2]
