RobA-

Good points. I think most of my political borders (as they appear on the sketch) follow your guidelines. Its just not so apparent, because mountain ranges, etc are still in my head!

The Keltoi / Ilium (Celtic and Greek) border actually cants clockwise a few more degrees to follow the mountain range that occurs along the fault line... The Keltoi / Skagen (Celtic / Viking) border is a point of conflict, with the Keltoi being nomadic and the Skagen starting to establish coastal settlements - there will be a narrow "no-man's land" as you call it (I've been thinking of it as a DMZ! =) along the northeast coast there. The only other political border within a geographical mass is in the southwest, where the two pre-Mayan-inspired civilizations share mostly peaceful borders on bodies of water.

The thought on the Imperrium Toranum (Roman-inspired) is that it thins out as it progresses into the shattered lands - there may be a technical "border", but it is not a Hadrian's Wall sort of situation, rather a "more civilized" (safe) and "less civilized" (not safe) one.

PD