Born amid the ruins of the great Roman Empire, Byzantium was, throughout more than a thousand years of its history, the scene of constant invasions, sieges, and wars. The boundary between West and East, the symbol of the Christian world—Constantinople—lured invaders with its wealth and splendor. How did the Byzantine Empire, once holding half the world, manage to endure so remarkably long despite every upheaval—and why did it eventually disappear almost without a trace, as if dissolved? The ancient state was not saved by its powerful army, the skill of its politicians, the impregnable walls of Constantinople, nor by the belief that God would not abandon the first Christian empire on earth—spreading the new faith not only across its vast territory, but also in neighboring states. How Byzantium was founded, how it ruled the world, and how it perished—what legacy it left to the modern world—British historian Jonathan Harris tells.