Politheist religions began merging their gods, having fewer and fewer with the passing of centuries or even millennia. I’m not talking about Greek or Egyptian gods, but the gods of the isolated and different tribes. With the commerce and war and syncretism of the conquerors these gods merge. Also, for economic purposes there was en emphasis on the individual contrary to the older gods which emphasized on the tribe. Here Christianity and other judeochristian religions were more skilled to give the universe and world purpose by relying in the already syncretized beliefs of other cultures. The book Homo Sapiens by Yuval Noah Harari explains it better