>>938390451
Basically, 2000 years ago, the Jews had this religion with a lot of potential that could convert a lot of pagans, but it was unable to realize it because of the whole "chosen people" thing restricting it to a tiny little group in the Levant.
Why could it so effectively convert pagans? Because it was far more existential, i.e. concerned with the nature of the soul rather than just material things like harvests, and its claim of "one true God" gave it a sense of veracity less existential religions lacked.
So, Jesus (or, rather, his apostles) created a new religion, which was basically the same religion, except without those pesky ethnic ties. Now, it could spread like wildfire.
By the end of the 20-year reign of the Roman emperor Constantine (the first Christian emperor) in 337, Christianity had gone from being a minority religion, to being practiced by at least 50% of the people in the empire, and by 395 this number was 90%.
Why was Christianity so successful in the Roman Empire? There is not a single answer. Aside from what I've mentioned above, it due, in part, to Christianity's willingness to adopt the customs of the empire. Some of it also has to do with the weakness of the pagan religions and the urban elites, who were these religions' chief supporters.
Christianity (and later Islam) would never had been so successful were it not for the Roman empire.
So, not only is Christianity's dominance attributable to based Romans, Jesus was basically the first CEO. I guess. The CEO thing made more sense in my head. I stand by the rest, though.