Let me give you an example of the kind of weird stuff that happened in the period on the edge of TESTAMENT...
After Alexander the Great (what a movie...

) conquered the Persians, a priesthood of Alexander was established. There were shrines and priests to Alexander in different places in Egypt and Greece.
But in a D&D world, nobody would follow a priest who couldn't cast spells, right?

So this means that either the deification of Alexander (and other famous people, like the Roman emperors) probably wouldn't happen... OR somehow, priests could actually get spells by praying to the "demigod" Alexander. Bizarre.
Another weird thing: the process of "assimilating" Gods together. This happened in ancient Egypt, with gods like Amun and Ra being gradually joined together to create "Amun-Ra." Later on, Zeus also got associated with Amun. It's kind of like the New-Agey "We're all really the same" motivation that underlies the merging of religions today.
In D&D terms, this would have to mean... !??! I don't even know what this would mean!

Strangely enough, though, EGYPTIAN ADVENTURES actually had rules for this. (Their idea was that it was just the result of the human priests not really knowing what the deal was... but they could still get low-level spells by worshipping "composite gods" since the individual gods were real.)
Yes, ancient religion is strange.... and not entirely easy to D&D-ize...
Hmm... why did this thread get moved, I wonder? :/
Jason