Christianity in Turkey
Constantinople became established in the ecclesiastical hierarchy at the Council of Constantinople in 381. Second only to Rome, the legendary origins of the Patriarchate of Constantinople go back to St. Andrew, Metrophanes and Alexander of Constantinople. Constantinople's primacy over the Patriarchates of Alexandria and Antioch was reaffirmed at the Council of Chalcedon in 481, after which the papacy in Rome supported Constantinople in its dispute with Alexandria over monophysitism. Later, when Rome sought to assert its primacy over Byzantium, the Eastern Orthodox church developed the doctrine of pentarchy as a response.
Constantinople
Constantinople was the largest and richest urban center in the Eastern Mediterranean Sea during the late Eastern Roman Empire, mostly as a result of its strategic position commanding the trade routes between the Aegean Sea and the Black Sea. It would remain the capital of the eastern, Greek-speaking empire for over a thousand years. At its peak, roughly corresponding to the Middle Ages, it was the richest and largest European city, exerting a powerful cultural pull and dominating economic life in the Mediterranean. Visitors and merchants were especially struck by the beautiful monasteries and churches of the city, in particular the Hagia Sophia, or the Church of Holy Wisdom. According to Russian 14th-century traveler Stephen of Novgorod: "As for Hagia Sophia, the human mind can neither tell it nor make description of it."