I have basically the same idea about the geography of the great cycle as Forrest; each Great Hero arises in the region which that time's Leveller attacked last (because this is the only region which still offers the possibility of a Light victory, everywhere else having been devastated), and then attacks his birthplace first when he's possessed in turn (because he knows it best and so finds it easiest to conquer, because its people are the most trusting of him and so are easiest to initially deceive, and because it's usually on the edge of the continent and so he can conquer it without alerting all the rest of the Light-dominated lands.)
So yeah, I think that Balor conquered Gower first. And just as the West remained free of the Dark until the very end of Balor's rule, so Gower will remain under Dark control until just before Alric is possessed by the Leveller. Over the next 400 years, Alric will extend his dominion eastward, liberating the people from the remnants of the Dark (if there's anyone left to liberate; the rest of the continent may be as lifeless as the Cath Bruig). Just after he gets to Gower, he'll be possessed and return to the Province or thereabouts, establishing his Dark empire there.
I think it's very likely that the two missing Fallen Lords are hanging out East, around Gower. If there's anyone still alive there (the Dark may keep a population of humans alive in order to be harvested as food for the Ghols and to be killed and resurrected as undead warriors), they'd probably revolt if at least one Lord wasn't there to keep them down.
--SiliconDream
