[momoschili]

Many Western polities have sought the title of the Roman Empire and the legitimacy it endows. Constantine split the empire, and Constantius II did not rule over Rome (or many other parts of the empire). Is it even reasonable to assert it was still the Roman Empire after the fracture?

Is it legitimate for the Eastern Roman Empire to claim the legacy? I think so, and I think they have among the best arguments for it. Conversely it is also legitimate to note the major differences between the two and the fact that discontinuities do exist.

[derdi]

"Constantine split the empire" is just incorrect. There were co-emperors with regional responsibilities both before and after him. They were co-emperors of one empire. If you want a firm split, 395 (death of Theodosius) is the more common date AFAIK.

I'm not denying that gradually, over well more than a thousand years, the empire (only surviving in the East) changed character in many ways. I am denying that a unique Eastern character sprang up (and immediately applied to Egypt) the moment that Constantinople was founded.

[brudgers]

Also worth noting that Roman tradition was for two Consuls at a time.

[momoschili]

You're correct, I'm mistaken that Constantine split the empire. That being said I think there are some semantics as far as "co-emperors with regional responsibilities" being in a single polity or separate polities.

I do agree with you that there was no instantaneous Eastern character that sprang up out of nowhere.