Im just adding an opinion here, but I think that Hoggy's original concept, with a few added embellishments would fit perfectly with the half realistic, half fictitious feel of this mod that seems to draw everyone's attention. A slightly, or even non-modified map of Eastern Asia could suit with Japan and China in their normal places, and the Demons serving as invaders from the north (which characterized much of actual Chinese and Japanese history). The gods could be in the middle, as hoggy mentioned, probably in northwest China, or even Korea, which would set them off from the battle areas, but still in the middle of the three. I was thinking, however, that each faction could have a or many patron gods which support their faction and serve as the Senate. This would not be too far from popular folklore, now that I think of it, from the Classical era, in which the gods stayed north and away from the Greeks and Trojans; while some supported the Greeks and others the ill-fated Trojans.

Just an idea..