With incisive commentary, Professor Madden leads a discussion covering Justinian's re-conquest of the West, the great city of Constantinople, and the aftermath and influence of this extraordinary empire. The term "Byzantine" was invented by modern historians to identify the final millennium of the Roman Empire. By the third century and into the fourth century, there were changes in the Roman Empire so profound that historians during the Enlightenment began to call the period Byzantine rather than Roman. Most historians would place the beginnings of the Byzantine Empire roughly around the reign of the emperor Diocletian, who instituted widespread reforms to halt civil wars and economic decline.

One of the primary characteristics of the Byzantine Empire was the relegation of Rome to a place of honor only. Rome was not the capital of the Byzantine Empire. The capital, instead, was Constantinople. Therefore, power was based in the eastern Mediterranean. Next was the dominance of Greek culture and eastern perspectives, and a final characteristic was the integration of Christianity into the social and political fabric of the empire. Constantinople was the beating heart of the Byzantine Empire and the greatest city in the Western world at this time. Constantinople sat at the crossroads of the world and controlled east-west land traffic. Eventually, the fall of Constantinople to the Ottoman Turks reverberated across the Christian world. Europeans now saw a world in which nothing stood between them as the last remnant of free Christendom and the ever-growing powers of Islam.