Note that this is a map of Europa two years after the event in the first game /manga /anime. It gives us a good idea of how EW II turned out for the Empire and the Federation outside of the Gallian theatre of operations.
It's somehow interesting because the cities that are mentionned on the map are different from those in the maps from the first game (as you can see on the
wallpapers on the game's website).
Kira, I wouldn't try to identify countries in the VC universe to any existing European country. This is quite a psychedelic representation of the continent, with proportions stretched in all direction and existing city and sea names pasted all over.
(had a snicker there when I saw that the small Swiss wine-producing village of (st-)Saphorin was a major Federation city).
After all as someone else pointed out Welkin Gunther is based on the Gaul historical figure of Vercingetorix. The Empire and Federation might aswell be a modernised Germania and Roman Empire. Most likely though it came entirely out of the designer's head and they just put it at the most conveniant place on the map without relation to the real world.