The Orthodox Church is the Church founded by the Lord Jesus Christ Himself, through His Apostles, at Pentecost. After this, the Apostles went out and made “disciples of all nations” (Mattew 28:19, Acts 2:8), establishing the Christian Church throughout the ancient world: St. Paul established the Church of Antioch; Saints Peter and James the Church of Jerusalem; St. Andrew the Church of Constantinople; St. Mark the Church of Alexandria; Saints Peter and Paul the Church of Rome.
Throughout the first 1000 years of Christendom, there was “One, Holy, Catholic, and Apostolic Church.” She is One, because she was founded by the one and only Savior; She is Holy because He is Holy and the Holy Spirit dwells in her; She is Catholic, meaning universal, in that she holds the same beliefs everywhere; and She is Apostolic because Christ founded her through the Apostles, who ordered and organized her, and she continues in their teaching (Ephesians 2:20).
The word “Orthodox,” which means “right belief,” was used in the early Church to distinguish the true believers from those who had departed from the tradition of the Church, the teachings of the Apostles.
The Western or “Roman Catholic” Church officially separated from the Orthodox Church in the year 1054 after adding the “Filioque” to the Nicene Creed (thereby altering the established statement of beliefs of the Church) and claiming the primacy of power of the Bishop of Rome (the Pope) over the other Bishops. The Orthodox Church does not recognize a universal head other than Christ. Instead, it is composed of several self-governing churches (Greek, Russian, etc.) held together by unity of faith and sacramental communion.
The Roman Church continued to move further from the united body of Christ with various changes in doctrine and practice. These changes resulted in the Protestant Reformation which scattered the Western church into thousands of sects. In the meantime, however, the “One Holy Catholic and Apostolic Church,” the Orthodox Church, continued and continues to flourish. In Greece, Russia, Serbia, Romania, areas of the Middle East and Africa and elsewhere, the faith of Christ remains the same. Orthodoxy now flourishes in America as well, and has for over 200 years.
Timeline of Church History
33 Christian Church begins
312 Constantine establishes the Byzantine Empire
787 Last of Seven Ecumenical Councils which establish the faith and root out heresies
988 Conversion of Russia begins
1054 The Great Schism, the Roman Church separates
1204 Rome sacks Constantinople in the Crusades
1517 Protestant Reformation begins
1529 Church of England splits from the Roman Church
1794 Russian missionaries establish Orthodoxy in America
1795 Methodist Church splits from the Church of England following the death of John Wesley
1830 Mormon Church is founded in America
1863 Seventh Day Adventists church is founded
1879 Christian Scientist church is founded
1901 Pentecostal movement begins
1960s “Jesus Movement” begins
2000s Estimated 35,000+ denominations in the U.S. alone
For more on the history of the Orthodox Church in North America check out, A History and Introduction of the Orthodox Church in America.