[krapp]

I think what matters in the case of the Abrahamic religions (or any religion) is the power of the military that spreads it. Christianity was forced onto the Western world by Rome and later Spain, Britain, Portugal and other powers as a means of consolidating imperialist control and the slave trade.

But remember a similar process happened with Buddhism and Confcucianism across Asia. Native religions were oppressed and state religions established.

[elcritch]

Partially true, but it's more complicated than this. Especially for Christianity.

Christianity did spread initially through the Roman empire despite broad persecutions by the state until Constantine legalized it. There's also evidence Christianity spread to Europe in the 2nd century before Constantine. It also spread to Ethiopia, Assyria, and even India, mostly by trade routes.

Christianity afterwards did spread with various European empires, but it also acted as a restraining hand as well. Some Christian missionaries went against the colonial states, in particular Protestant ones.