Actually, religion has its origins back in Neanderthal times, if archaeology is any testament. It's not uniquely human, we were the second bipedal ape to have the idea. Religion in the sense that we think of it is no older than the 19th Century, in days gone by it informed all aspects of all levels of society. Indians and Aborigines are just as religious as Christians, it's just that traditionals of both cultures adhere to the older ethnic-regional model of religion.

Extremely hierarchical societies are a rarity and do not tend to have real staying power in human history.