<P> 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 , Hagia Sophia , or the Church of Holy Wisdom : A Russian 14th - century traveler , Stephen of Novgorod , wrote , `` As for Hagia Sophia , the human mind can neither tell it nor make description of it . '' </P>
why was constantinople an important center of european trade
its strategic position commanding the trade routes between the Aegean Sea and the Black Sea