Consider why the Roman public, commoners in particular but not exclusively, were so ready to abandon the religious beliefs of their forefathers and throw it all away, even defacing the old temples, to adopt some jewish desert hippie's promise of simple salvation. Perhaps you'd like to think this conversion of Rome was all by the sword, but in reality the early christian converts chose despite very credible threats of state violence, and the state itself only converted when the critical mass of common christians could no longer be denied or ignored.
Rome's culture and traditional was fundamentally broken; it no longer served the needs of the Roman people, and if Christianity hadn't popped up, it would have been some other system of reform instead. The status quo was unstable, rapidly deteriorating. You may idealize the religious tolerance of their polytheism, but what that matter if it isn't actually serving the spiritual needs of the people?
" You may idealize the religious tolerance of their polytheism, but what that matter if it isn't actually serving the spiritual needs of the people?"
Rome in the end was a decadent, but brutal empire full of slaves. And to a slave christian salvation sounds great.
But before there was a empire with emperors taking up the idea of becoming gods themself, there was a republic. And also after it became an empire, they did not have a institution like the inquisition shaping thought and banning heresy baked into their system.
This is the fundamental difference that I see.
In medieval times being expelled from the church was pretty much a death sentence. In roman and greek times for most of its existence not really.
The demise of the Roman Republic was an inevitability. It could have been Sulla rather than Caesar, and if not Caesar it could have been another, but one way or the other the situation was fundamentally unstable and the public was deeply discontent. Would be reformers like the Gracchi were finding enormous popular traction only to get assassinated.
Also, the Roman Republic were prolific slavers too. I say this because you speak of the Empire and slavery but then go into a "But the Republic.." This isn't Star Wars, you can't divide it into good guys and bad guys, the Republic and Empire were both imperial sons of bitches who conquered territory and took civilians as slaves. The demand for reform that would eventually motivate mass conversions to Christianity was already well established before Caesar was even born.
"Also, the Roman Republic were prolific slavers too. I say this because you speak of the Empire and slavery but then go into a "But the Republic..""
My point here was about freedom of thought. And that seems to have been way more valued in the republic, than in the empire. (In general, good and bad are relative terms to me)
"The demand for reform that would eventually motivate mass conversions to Christianity was already well established before Caesar was even born."
And maybe so. But christianity in general was not really about freeing slaves, either.
Rome's culture and traditional was fundamentally broken; it no longer served the needs of the Roman people, and if Christianity hadn't popped up, it would have been some other system of reform instead. The status quo was unstable, rapidly deteriorating. You may idealize the religious tolerance of their polytheism, but what that matter if it isn't actually serving the spiritual needs of the people?