in very early times, when the first humans were becoming social and civilized, some of the craftiest among them realized early on that people could be minipulated. everyone has a talent, you know. some people are born leaders and polititions.
it was these men that usurped man's natural inclination to wonder and speculate on the unknown and supernatural. and they exploited it with an organized religion that taught men the virtues of conformity and reliance on belief systems for savior.
everything in this universe evolves. and those belief systems which were better able to adapt survived and were more popular. We still have many today. Christianity was great spin on the old Sun worshiping religions. And it has lasted 2,000 in this form.
The control over humans is the reason religion was seized upon and implimented by the ruling elite of almost every nation of history, barring a few recent ones. And there are still myths that the original 12 families of those early manipulating rulers of humans still exist and operate behind the scenes in positions of power over men. why not? they were, of old, the richest, most powerful men alive. when they live and then die, their money, power, influence and knowledge is passed on to their heirs.