'Ancient' religions tended to be more based on science - witnessing and celebrating the changes of the seasons and the forces at work in nature - they didn't have science to explain this but gave the forces at work arhetypes. Many of the old religions also took into account the human condition - using archetypes to explain personality traits - loving, violent, mad, forgiving, optimistic, sanguine, introverted etc. In those days there was no school of psychology. These were described as frequencies which we were effected by or waves and by altering the resonance in a person you could move them from one state to another. Much of this frequency base was used as polyrthythms in singing or music and it was these frequencies which were given names - like moods in music.
This pantheon of nature and aspects of the human soul were given names as gods - but not worshipped as a seperate entity until much later.
All religions had their central tenent the belief of no-thing from which everything came. Only with later religions was god removed from the workings of the universe and given 'his' own judgement or a set of rules to say if you were in or out of that religion and that's where it all went pants and people had to be believers or not - before that you could believe the sun wasn't going to come up or winter wasn't going to come but you'd have been wrong.
Many early religions used the understanding of the human conditions and the 'spirits' effecting the psyche, so that their shaman or priests could either work cures using the only things they understood cause and effect - they aren't called medicine men without good reason - it's just we've replaced them with doctors, the caduceus isn't on the side of ambulances and in hospitals for nothing. The cross with two entwined serpents made sense and was in many religions. Only with christiantiy were the serpents removed and healing became 'faith' and not medicine.
Priests also had an understanding of 'bonding' and the human condition to enforce 'tribal influences' and community' and thuse rituals, celebrations and ceremonies were born - without these we'd have no music or festivals. With this came the rules of life - to keep social structure and provide the basic morality of life. It was also this that the priests realised equal power and thus the gods were corrupted and the bloodshed started.