'Everyone's a pagan now'

[Cato]

I think that Christianity was better suited to gaining temporal power over the carcass of the Roman empire. Like Ottar said, Zoroastrianism was tolerant of other religions, which would have defeated the whole purpose of creating a state religion to replace the mishmash of local and tribal religions and thereby attempt to restore some unity and cohesion to the empire.

Having considered Mithraism, I know that it was a religion of equity and tolerance. Slaves, freedmen, citizens and even royalty all rubbed elbows in the mithraea. Some commentators have pointed out that this broad-mindedness was the religion's undoing. Can fraternal tolerance really defeat intolerant single-mindedness such as the fanatics of Christ displayed once they finally won out at Rome? Even a militant religion like Mithraism, which seems to have had no real central authority, would go under pretty quickly to well-organized strikes by the fishermen- as in fact happened because, while some pagan religions like the Isis cult, held out for a couple of centuries into the 500s or so, Mithraism seems to vanish at about the time the empire became officially Christian in the Constantinian years.