Many historical cultures in the hunter-gatherer neanderthal stages have left no evidence they were involved in spiritual belief systems. Read Jared Diamond's Guns Germs and Steel or any book on pre-civilization. And while it's easy to point out that some early groups had individuals that had what we may call superstitions, many other groups showed no signs of such beliefs. It's just a non-issue. We learn from them what little we can from the remnants left behind and if religious and superstitious ideas were not one of them, then it's not a mentionable item to most historians.ust because one group here or there did, doesn't mean every group everywhere 60,000 or 100,000 years ago did. The small but scattered amount of findings that showed the existance of man in those eras, may have shown where one family lived or ate, but little was left that indicates anything whatsoever about worship or beliefs. To state otherwise is beyond conjecture.
What is notable is the rise and increase of supersticious relics from an increase in Agricultural based communities. The dramatic increase is not correlated to a population rise either, and thus conclusions can be drawn about the development of human thought, particurlarly as more time became availalbe to allow for the beginings of the formation of civilization.
So while certainly you can say as civilizatioin began to rise so did the increase in people desiring answers to events occuring without obvious cause. Many invented supersticious beliefs systems to help them cope. But very few individuals, civilized or otherwise would just naturally grow up and say - I think there's a spiritual realm out there. Those ideas are planted from others - and more prevelantly so in civilized-type societies.
Neither can you discount the many that just didn't feel a spiritual, never felt a need to attribute things they didn't understand to the supernatural, and just simply weren't implanted with other's invented spiritual ideas. Many ancient greeks, Indians, Chinese, and others, from the dawn of their independent thinking, raised families without passing on the idea of the supernatural. These folks didn't question gods - but were rather questioned by other believers about their naturally inclined stance not to have any spirituality. Basically, without an implantation of invented supernatural ideas - "untheism" is a more natural state for humans, and appears to have been so for a long time both pre-civilization and often throughout civilization's rise.
Nevertheless, the idea that many cultures did seem to invent supernatural explanations helps many accept their own beliefs passed on to them from others. Jehovah's Witnesses are among those as are probably many other believers. I heard that line of reasoning my whole life. I took a tour at the British Museum and it was constantly thrown out there, about these ancient civilizations and people with their belief systems and how Jesus words about ' "happy is he who is conscious of his spiritual need" rings true throughout history.' Some use the similar line of reasoning to justify their belief in the flood.
The point is, when you look closer at history, it's just not a very accurate assesment. Not discounting the rise of religious belief with civilization - but claiming ALL people since the dawn of man ... that's more than a leap. I don't want this to wreck anyone's faith though. I enjoy belief systems and magic and studying up on all of them. I respect the anchor that such beliefs are to many people's morality. I think, as far as it concerns them personally, they should indulge it and use it to seek out their best self for the greater good of society. The world, including history, might be a more boring place if everyone believed the same thing about the supernatural.