Without Christianity does Rome end up surviving longer and even if it still falls does it reuniting stay more likely. Rome can be taken over by invading barbarians but could they end up assimilating to Roman culture like invaders of China did? Could Rome go through warring states periods before going into periods of long unification and peace? Could you have both the Western and Eastern Empires do this at the same time if both stay separate? What happens with the rest of Europe and the mediterranean region in the coming centuries if a pod like this is possible?