Eastern Orthodox Church

The Eastern Orthodox Church, officially the Orthodox Catholic Church, also referred to as the Orthodox Church, Eastern Orthodoxy, and Orthodoxy, is the second largest Christian Church in the world, with an estimated 225–300 million adherents.

The Eastern Orthodox Church is one of the oldest religious institutions in the world, teaching that it is the One, Holy, Catholic and Apostolic Church established by Jesus Christ in his Great Commission to the apostles, and practicing what it understands to be the original faith passed down from the Apostles.

United in communion with the Latin Church before the East–West Schism in 1054, and with the Oriental churches for the first quarter of its history, Eastern Orthodoxy spread throughout the Roman and later Byzantine Empires and beyond, playing a prominent role in European, Near Eastern, Slavic, and some African cultures. Its most prominent episcopal see is Constantinople.

Eastern Orthodoxy has no Papacy or similar authority, but instead teaches that all bishops are equal by virtue of their ordination, and each autocephalous church is typically governed by a Holy Synod. This is one of the main reasons for the division between the Roman Catholic Church and the Eastern Orthodox Church. The commonly-used but unofficial designation "Eastern" derives from the geographical location of the main centers of Orthodoxy in relation to the "Western" churches (now known as the Roman Catholic Church), and from Constantinople being the capital of the Eastern Roman Empire.

Catholic Church

The Catholic Church, also known as the Roman Catholic Church, is the largest Christian church, with more than 1.25 billion members worldwide. One of the oldest religious institutions in the world, it has played a prominent role in the history of Western civilisation.Headed by the Bishop of Rome, known as the Pope, its doctrines are summarised in the Nicene Creed. The Catholic Church is also notable within the Western Christian tradition for its celebration of the seven sacraments.

The Catholic Church teaches that it is the one true church founded by Jesus Christ, that its bishops are the successors of Christ's apostles, and that the Pope is the successor to Saint Peter. The Church maintains that the doctrine on faith and morals that it declares as definitive is infallible. The Latin Church, the autonomous Eastern Catholic Churches and religious institutes such as the Jesuits, mendicant orders and enclosed monastic orders, reflect a variety of theological emphases in the Church.

Byzantine Empire

The Byzantine Empire, sometimes referred to as the Eastern Roman Empire, was the continuation of the Roman Empire in the East during Late Antiquity and the Middle Ages, when its capital city was Constantinople (modern-day Istanbul, originally founded as Byzantium). It survived the fragmentation and fall of the Western Roman Empire in the 5th century AD and continued to exist for an additional thousand years until it fell to the Ottoman Turks in 1453. During most of its existence, the empire was the most powerful economic, cultural, and military force in Europe. Both "Byzantine Empire" and "Eastern Roman Empire" are historiographical terms created after the end of the realm; its citizens continued to refer to their empire as the Roman Empire (Ancient Greek: Βασιλεία τῶν Ῥωμαίων, tr. Basileia tôn Rhōmaiōn; Latin: Imperium Romanum), or Romania (Ῥωμανία), and to themselves as "Romans".

Several events from the 4th to 6th centuries mark the period of transition during which the Roman Empire's Greek East and Latin West divided. Constantine I (r. 324–337) reorganised the empire, made Constantinople the new capital, and legalised Christianity. Under Theodosius I (r. 379–395), Christianity became the Empire's official state religion and other religious practices were proscribed. Finally, under the reign of Heraclius (r. 610–641), the Empire's military and administration were restructured and adopted Greek for official use instead of Latin. Thus, although the Roman state continued and Roman state traditions were maintained, modern historians distinguish Byzantium from ancient Rome insofar as it was centred on Constantinople, oriented towards Greek rather than Latin culture, and characterised by Orthodox Christianity.

Ruthenian Catholic Church

The Ruthenian Catholic Church (also known as the "Byzantine Catholic Church" in America) is an Eastern Catholic Church that uses the Byzantine Rite in its services. It is one of the 23 Eastern Catholic Churches that is in full communion with the Holy See. There are two main communities within the Church - American and European. In the United States, the Byzantine Catholic Metropolitan Church of Pittsburgh is self-governing (sui iuris). In Europe, Ruthenian Catholics are immediately subject to the Holy See. The European branch has an eparchy in Ukraine (the Eparchy of Mukacheve) and another in the Czech Republic (the Ruthenian Apostolic Exarchate of Czech Republic).

The Ruthenian Catholic Church is rooted among the Rusyn people who lived in Carpathian Ruthenia. This part of the Carpathian Mountains straddles the borders of the present-day states of Hungary, Slovakia and Ukraine. Today, the Church is multi-ethnic. Members of the Metropolitan province of Pittsburgh are predominantly English-speaking. Most are descendants of Rusyns but the descendants of other nationalities are also present such as Slovaks, Hungarians and Croats as well as those of non-Slavic and non-Eastern European ancestry. The modern Eparchy of Mukacheve in Ukraine is mostly Ukrainian speaking and remains officially part of the greater Ruthenian Church.

Church History

Church History may refer to