that's a very ambitious we wuz map. realistically, it was czechoslovakia lands. but yes, there absolutely wasn't a "the romans" at the time, with franks and greeks fighting on the battlefield with steel and in the barbarian lands with missionaries and diplomats. of course the people we call the byzantines were very well aware that they spoke greek and called themselves with greek names. they called themselves romans like how the ottomans called themselves romans (or the russians even), it was a territorial claim and not a claim to nationhood.
Bulgaria