In the flourishing schools of Constantinople the wisest men of the day taught philosophy, law, medicine, and science to thousands of students. The professors figured among the important persons of the court: official documents mention the “prince of the rhetoricians” and the “consul of the philosophers.”

Many of the emperors showed a taste for scholarship; one of them was said to have been so devoted to study that he almost forgot to reign. When kings in western Europe were so ignorant that they could with difficulty scrawl their names, eastern emperors wrote books and composed poetry.

It was Justinian who, after Constantine, did most to adorn the new capital by the Bosporus. He is said to have erected more than twenty-five churches in Constantinople and its suburbs. Of these, the most beautiful is the world-famed cathedral dedicated by Justinian to “Holy Wisdom.” Though nearly fourteen hundred years old and now defaced by vandal hands, it remains perhaps the supreme achievement of Christian architecture.

Throughout the Middle Ages Constantinople remained the most important city in Europe. When London, Paris, and Vienna were small and mean towns, Constantinople was a large and flourishing metropolis. The renown of the city penetrated even into barbarian lands. The Scandinavians called it Micklegarth, the “Great City”; the Russians knew of it as Tsarigrad, the “City of the Caesars.” But its own people best described it as the “City guarded by God.” Here, for more than eleven centuries, was the capital of the Roman Empire and the center of Eastern Christendom.

From The Making of Europe / Early European History