Not entirely sure, although I am fairly certain that the belt ranking system is a modern invention - used to be that a black belt was a black belt, whether you had been studying for 5 years or 50. My understanding is that belts were never really meant to signify any particular kind of "rank", but were a means of organizing students so that instructors could keep track of who had been taught what (sort of).
KMA do have a history that goes way, way back, and the name they have for most of it is something like Taekeon (sp)? There is also an ancient Korean wrestling art, but the name escapes me. Hapkido is Daito-Ryu Aikijujutsu in its initial form, with the more recent styles being the ones that have the dynamic offensive techniques included.
Historically, if you follow the patterns/lore, most martial arts went from China to Korea to Japan, but when Korea went Taoist most of their arts died out, with the exception of a blend of several styles that were taught to the Hwarang (the young, promising soldiers, not religious monks, and no, it's not Hwarang Do). Then the Japanese came and tried their hardest to eliminate what was left. All of the Korean arts, with the exception of a couple of weapons, are now mostly of modern Japanese and Chinese origins. Korean Kung Fu, or Ship Phal Ki (spelling?) I think is a derivative of Mantis (I can't remember whether it was Northern or Southern) and/or Long Fist (of which there are several variants). TKD, as far as my reading has led me to believe, is Karate with a bit of Taekeon and a few other pieces tied in, and it's kicking heavy, because like the historical KMA book mentioned earlier in this thread, Korean generals (old and new) expected that their soldiers would be carrying a weapon. It has, of course, evolved quite a bit since then. Since TKD is only a part of my training, I'm not fully versed in all the techniques, but I do think that its effectiveness is underrated - largely because of the explosion of mcdojangs and the western belief that anyone speaking with an asian accent is some sort of zen shaolin chi master that can shoot shoryuken fireballs from their fist and kill with the evil eye.
I'd bet you my next paycheck that I could ask any one of the 50 soccer moms that drop their kid off at the dojang where I train if they knew what kukkiwon was, or korea hapkido federation, or if they knew if Master Kwon is/was certified, or even what martial art their child is studying, they wouldn't know. It's so frustrating...but I digress.
