Well since we all come from someone giving birth it makes sense to keep tracing your lineage farther/further back to eventually wondering who "birthed" the first person of your ancestry. Then tales will spawn in substitution for facts/knowledge about your first ancestor.
Religion shows people a lot about themselves. Like what they are willing to accept as true or false, fact or fiction, and good versus evil. Seeing someone's actions to preserve religion versus someone's actions to preserve life can make a big impression.
The big thing involves death and potential life after death and the fear and uncertainty surrounding it all.
It may or may not be needed , but if it turns out that "GOD" or the religious text were true, then they really will be a little more than a history book probably.
It isn't really needed, but it can help. We have nature all around & in us , and just adapt to things, we don't really need "religion" or "belief in a supernatural being" to "function" or be "better" people. People who have faith in "GOD" don't really "know" for sure either.
We're all here and all going to die , but being religious doesn't really add anything to life except and adjective. Atheists, agnostics, and the religious all live and die the only way people are capable.