The main ideal was that the god guarded the valuable metals and ores of the mountain and cave-ins and equipment failures and other calamities where his way of getting back. Proper sacraments and rituals would please the god and he would grant rich ore seams to the miners. Part of these sacraments included the construction of idols that would be placed in alcoves around the mine and granted gifts of small gems, cigarettes (which would be put in the mouth of the idol and lit), alcohol, and meat.
That's the most DF like real life thing I've heard of. Awesome. We so need functional gods in DF.
IIRC, a lot of early Mesopotamian religions were like that. More like buying "insurance" from organized crime than asking for favors.
I was just thinking about that in response. The one I remember in particular was the Babalonia god Nargal, lord of war, plagues, pestilence, and the fierce summer sun. I'm hardly a scholar, but I given what else we know of ancient mesopotamians, I'm guessing people weren't worshiping him out of pragmatic suplication.
And yes, Games Workshop appropriated him into Nurgle, since in twenty five years of writing they've had about three original ideas.