Simple: Religious Culture. The culture shifted and many people (consciously or subconsciously) followed the culture when it shifted. Either from cowardice, survival, or originally followed, most of these people switched to this new religion and fully believe it.
Simple: Religious Culture. The culture shifted and many people (consciously or subconsciously) followed the culture when it shifted. Either from cowardice, survival, or originally followed, most of these people switched to this new religion and fully believe it.