The Byzantine Empire was the Roman Empire — calling it 'Byzantine' is an invention of historians long after the empire collapsed, and the people of that time always considered themselves Romans.
Kaldellis argues that the burden of proof is on those who claim the Byzantine Empire was something other than Roman. The Eastern Roman Empire called itself Roman, its subjects were Roman citizens, and the term 'Byzantine' was a Western European invention for political reasons.
transcript
Anthony Kaldellis: So, Lex, the burden of proof is on those who would assert that what we've been calling the Byzantine Empire is something other than the Roman Empire, because all of our sources are very clear about this. And we've known about this. We've always known about it. It's almost a form of cognitive dissonance, right? It's like when you know something is the case, but you carry on as if it's not. So the Eastern Roman Empire, this is the direct continuation of the ancient Roman Empire in the East, right? Everybody knows the Western Empire fell in the 5th century. And for many conceptions of Western history, that was sufficient. Like that's when we just called it the Roman Empire fell in the 5th century. And we kind of, yeah, we kind of know that the Eastern half survived, but we don't want to include that in our cultural genealogy. And so we kind of pretend that it became something else. But in fact, it called itself the Roman Empire. Its subjects were Roman citizens. They called themselves Romans all the way down through to the end and beyond.