I'm trying to find a (somewhat) detailed explanation on why and how these two schools of design diverged and developed, but haven't really been able to come upon one to date.

Do any of you happen to have the knowledge along with some time to kill writing about it? Or do any of you happen to know of any books/article/web pages that give a good explanation of not so much just what the differences are, but of why they ended up that way?

I'm also curious if any other regions of Europe had interesting local variations on those two dominant styles. I haven't been able to find out much on this either.

Thanks for the help, if anyone does know about any of this or can point me to a good source. Much appreciated.

Well as for other regional styles, Tobias Capwell has a book out on English armour.