Summary: Do centaurs come in Palomino? Hell yeah, they do.
A common theory about the origin of the centaur myth is that it's rooted in a non-riding culture's first sighting of a mounted rider, such as a warrior of the Scythian people who lived a horse-taming and riding life on the steppes of what is now modern day Kazakhstan, Russia and western China.
Arthur's tattoos are Scythian in origin, these ancient designs have been found tattooed on excellently preserved Scythian mummies, male and female. The Scythians had no written language, but it appears that beautiful animal designs adorned them in life as they do in death.
It's easy to imagine the ancient Greek culture's first contact with these horse-breeding nomadic tribes of the steppes, which might well have inspired a storyteller of the ancient world to tell a tale which still survives, giving us the legend of the centaurs: mythical beasts half-man, half-horse, intelligent as they are fleet and ferocious in battle.
ETA: OH GOD. Almost forgot the MOST IMPORTANT part. The part where I thank amphigouryfor talking me down off ledges, for being a wonderful Beta, and for putting up with my crap. Thank you, Amph! ♥
Larger version on DA | My LJ