ABSTRACT
The reforms of Diocletian and Constantine added another 150 years of life to the ancient Roman Empire. Yet, the legacy of Constantine has lasted all the way from antiquity clear up to the present. The reign of Constantine, in fact, marked the climax of ancient classical, the middle of early Christian, and the beginning of Byzantine imperial and medieval European history. His personal conversion to Christianity and public patronage of Catholicism transformed the Christian Church from a persecuted minority cult into an established majority religion, and changed the pagan empire into a Christian commonwealth. Constantine established the Church in the world so firmly and helped it define its doctrine and develop its practices so fully that it was able to survive the vagaries of barbarian invasions and political upheavals during the late antique and early medieval centuries and become the defining institution in the Greek Orthodox empire of Byzantium and the Latin Catholic kingdoms of Europe for a millennium (ca. 450-1450). And as the Byzantine Empire was the civilizer of the southern and eastern Slavic peoples, and the Catholic Church was the civilizer of the northern Germanic and western Slavic peoples, the legacy of Constantine has extended through them to the countries of modern Europe and to their political and cultural offshoots across the globe.1
