Well, that's the point. If you know barely anything about today's political geography and you look at EUIV, you immediately recognize some of the polities we have today in it. On the top of my head, you can recognize (in no particular order) : France, Croatia, Serbia, Portugal, Hungary (bigger), Denmark, Norway, Sweden, Poland, Georgia, (weirder), Lithuania (immense), Turkey (immense), China, Japan (imploded), and also Great Britain (even though it's divided), Spain (also divided), the Czekh Republic (with a different name), Tunis, Kongo, Mali and a few others...It just does not mean you are aware about the history of most countries in the time period. Don't tell me the common knowlege about EU IV is higher than about the time period in imperator Rome. When i like the period i know the tags. When i dont, i know about EU IV also not much. I just compare the tags with modern nations.
In Imperator, you will recognize Egypt and maybe Makedon if you aren't a greek