User blog comment:The Devil's Advocate WP/The Historical Geography of Remnant/@comment-75.44.38.210-20140903193938

I agree with the idea that some of the regions that were on the map have sunk beneath the sea, but maybe they are not on the map for a reason.

Maybe they are secret facilities run be the four kingdoms to test weapons or act as high security prisons that they wouldn't want to display to the general public.