In this presentation, Professor Glen W. Bowersock discusses the emergence and interrelated fates of Rome, Constantinople, and Moscow. Rome became the capital of a great Mediterranean empire, which tried through myth and mystique to reconcile its legendary Trojan origins with its presence in Italy. As Roman power grew, the city's name became synonymous with the center of imperial government and, as Christianity grew, of ecclesiastical authority too. But when Constantine transferred the imperial capital to Byzantium and renamed the city after himself, Constantinople became a new or second Rome. For many centuries, this eastern Rome was both the capital of the Byzantine empire and the center of orthodox Christianity. It succumbed to the Ottoman Turks in 1453, and the Russians, who had accepted Christianity from the Byzantine Greeks, could then claim that Moscow had become the Third Rome. This lecture explores the implications of the triadic concept and the lessons it has to teach us about our past and our present.