In 1453, following the resettlement of the Italian Peninsula the City of Nova Roma was officially reverted back to Byzantium, itself a Latinization of the original Greek name Byzantion.
Reversion of ByzantiumAlthough founded by Byzas from Megara in 657 B.C., events really began to take shape in 196 A.D. when the Roman General Septimus Severus occupied the city. After ascending to the throne, he rebuilt the city and it prospered once again. Meanwhile, developments in Western Europe were going in the other way. Roman Emperor Aurelian was about to launch a campaign to retake the Gallic Empire when an inexplicable darkening of the day sky began in Western Europe.
Over several years, the hours of daylight steadily reduced, and agriculture began to fail. Fortunately, Aurelian successfully organized a mass eastward decantment and when this was completed, Byzantium was designated the official capital of the Roman Empire. Centuries passed and despite efforts to preserve this territory as a Roman-Empire-in-the-East, it soon took on many of the attributes of an Eastern Roman Empire. Because the Italian Peninsula contained the resources that had sustained the elite, and more than that, the new capital was still imbued with a pervasive Greek influence that drove out the Roman homogeneity. By the time that Western Europe was inhabitable once again, the imperium was for all intents and purposes a Second Greek Empire. A future split between East and West Roman Empires seemed inevitable.