Reimian Empire

Revan really managed to create unique countries because there isn't a clear parallel to draw.

I think it's more appropriate to draw parallels, not with real countries (excluding some), but with typical fantasy countries. For example, Rheims, no offense to Revan, plays the role of a typical fantasy empire. As an example, you can remember the Empire from Warlords. If you haven't played it, then remember, say, Erste from Granblue. Or, even simpler, Rheims is Illiniar with a couple of features from Nozenroth (high technology and racism (relatively towards the aridians and serpentfolk)). At least, that's the association I had.