Don't apologise so much, questions are to be encouraged!
The reasoning, I guess, is that when the Roleplay was originally created, there was a rush to have a working map as soon as possible, and not all thoughts were taken into account. It might have been more logical to have a few kingdoms only located on the Isles, and few kingdoms with no offshore territories, and perhaps some greater discrepancy between the nations in terms of size.
However, as I said, that sort of stuff really wasn't being thought out. Nathan's main intention in making the map was to make one encompassing all the factions, and giving the RPer a large enough space to play. In addition, when the Roleplay began, there were no pre-eminent nations. I suppose that it was also to avoid playing favourites that all the nations were given equivalently large pieces of land, split between the mainland and the isles.
As for explaining how all this is supposed to have ended up occurring within the Roleplay's history... that's what the Roleplay itself is for!
~Michael A. Joosten - Gaming Moderator~