Quote Originally Posted by iberus
but you must agree that cristianity caused extremely important unrest and unstability in the empire...
I don't exactly see how that's related to 'ruined the west'. Also, didn't one later emperor try to revert to paganism, which turned out to be extremely unpopular.

You could, equally, say that Christianity was what led to the Byzantines and Franks repelling the Muslims where the Pagans had been completely unable to.