Ex: People don't actually believe in Santa Clause, but if you randomly chose 10,000 pages to represent US thought from 1800 to now. Them handed them to scholars in the future there is a solid chance you they would assume it was the major religion.
I suspect sea monsters may simply be a similar tall tail and we lost context.
PS: Ok, we can reasonably assume people got hungry :D
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Anya: I love a ritual sacrifice.
Buffy: Not really a one of those.
Anya: To commemorate a past event, you kill and eat an animal. It's a ritual sacrifice. With pie.
"If you used historical techniques on us, you'd get completely the wrong idea!" Maybe. Or maybe you'd finally get the right idea.
I'd love to write more, but I've finished ingesting the stimulants that allow me to tolerate my oppressive culture (drinking coffee), and I'm going to take a short trip to worship the revered dead (visit the National Mall).
So, you have one God, but also a demigod, who is his son. There's a god of the underworld you call satan, and a number of divine or demonic creatures called angels and demons. Ok, throw in some ancestor worship in the form of saints.
This monotheistic pantheon would have sounded reassuringly familiar your ancient Greek interlocutor.
I agree that the Name of the Rose is not an historic work (incidentally so did Eco), but plenty of medievalists think that it is good enough to be a useful teaching tool:
http://www.syracuseuniversitypress.syr.edu/fall-2009/postscr...