What happened on Kobol?
I know the show never comes right out and tells us ALL of the details - and that is fine, ambiguity is not the worst thing in the world - but I'm trying to piece together roughly what happened after a recent re-watch.
I don't know if I forgot this or never picked up on it, but the 13th tribe, the humanoid cylons, left well before the other 12. I had thought they left as the result of a war between man and machine, but this doesn't appear to be the case? Or that WAS the case and then the 12 tribes left years later for another reason?