Is Atheism a Historically Contingent Concept?
I was recently thinking about the obvious fact that there couldn't have been a Frenchman 20,000 years ago, because there was no such thing as Frenchness as a social construct. This made me question my assumption about atheism. I always assumed that the very first gods must have had their doubters. That is to say, as soon as religiosity and spirituality became part of human culture, so too must have skepticism and disbelief. But I'm now questioning whether that's really correct.
What if atheism is like being French, in the sense that there was no "atheist" 20,000 years ago because it simply didn't exist as a social category, and was therefore outside the range of concepts people had available? Would people in the Paleolithic have simply accepted spirits, deities, or sacred places as being real, like trees, mountains, or rivers, without it being conceivable that they might not be? Or is it more likely that skepticism emerged alongside religious belief from the very beginning?
Obviously this is a highly speculative question, but I'm curious what anthropology tells us about the possibility of a lack of spirituality or religiosity in prehistoric societies, and whether "atheism" is even a meaningful concept to apply to such contexts.