Constantinople, now the Turkish city of Istanbul, was called after the Roman emperor Constantine the Great. The name means city of, Constantine. He was born at Nish in what is now Yugoslavia about A.D. 280 and was educated at the court of Galerius, the ruler of the Eastern Homan Empire. In A. D. 306 he was proclaimed Caesar:
At this time the Roman Empire was governed by four rulers, but the system did not work well, and Constantine decided there should be only one ruler-himself. He became a Christian as the result of visions he had seen promising him victory over his rivals if he embraced the new faith. Rome fell to his troops and in A.D. 323 the last of the independent rulers was defeated, leaving Constantine in command of the whole empire.
He changed the capital from Rome to the ancient city of Byzantium, on the shores of the Bosporus. He enlarged the city, renamed it Constantinople and enriched it with many churches and palaces.
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