Religions began as a way to keep husbands, wives, and children alive when those closest to them died (for whatever the reason)

 Here is the goal:so, anyway 

You needed enough people so your tribe didn't go extinct (from whatever the reason). So, any way you could convince people to stay alive (with truth or lies or half truths) was a way to keep the whole tribe alive.

So, the fairy tales flew fast and furious out of the Medicine men and women and tribal leaders mouths so their tribes could stay alive and prosper.

Also, you needed enough people to be good warriors to fight off invading hoards and to fight off large animals like Tigers and lions and Elephants and Bears and whatever else was there like Hippos and Crocodiles too.

So, the whole point would be having the tribe believe something, anything so that the tribe could survive anything it had to face from an animal hoard to another tribe to a pandemic to whatever.

So, medicine men and tribal leaders became more skillful over time in telling stories that might keep people alive.

However, it should also be known that up to 50% of what people were told was not true (And it is still this way today in religions throughout the world).

But, if you look at the motivations of people who made up these stories, mostly they didn't want their tribes to go extinct.

So, seen through these eyes: "Alls Fair in Love and War!"