In the latter 19th century, the History of Religions school took shape, and being avant-garde and willing to examine Christianity in the light of its (i.e., Christianity’s) own time and the expressions of that time, quite legitimately began to perceive all sorts of parallels and common elements between the Christ faith and the Graeco-Roman mystery cults. In some circles, that perception grew into a mania. It also adopted as a methodological assumption the idea that commonality equalled deliberate borrowing, in one direction or another. As well, similarities became equivalences. And what moved one people or one cult to formulate rituals and doctrines of salvation must have been operable across the board.