The Romans were well aware of mystery religions inside their borders, and Iudea was very much within the Empire’s borders, and many other religions became popular in the same period that Christianity did. For that matter, they were aware of religions outside of their borders too - there’s even some limited Greek and Roman writing on Buddhism.
Christianity had the good fortune of converting an Emperor (Constantine I) who imposed the faith on the whole of the Empire.
Paul
Also, the Romans were clearly aware of a lot of other religions.
In Caesar’s Messiah, Joseph Atwill argues the Flavians wrote most of the new testament.
As a solar deity, Jesus wasn’t “new”, they just re-wrote him as their favorite spin on one.
In Caesar’s Messiah, Joseph Atwill argues the Flavians wrote most of the new testament.
Uh, that’s a very… nonstandard and dubious position, for the record.
