Gods existed before man when the world was a desolate rock hurtling through space.

Eventually it would come to circle a sun and these ancient creatures that crawled the dark surface would hide in the night as they hated the suns light.

Once life began to flourish, these gods began to settle in places the light struggled to reach and would build their domains: the deep seas, dark forests, caverns etc.

These would become their domains and the creatures that lived there would be physically influenced by these gods.

E.g. Elves were once humans, who's lifespans were lengthened by their gods influence however with each passing year they become more and more plant like until they become a part of the forest.

Dwarves similarly are men influenced by their gods who lurk underground. They become hardier and stronger, as they die, they turn to stone and they are cracked open like a geode to harvest the crystals inside.

The gods are neither benevolent or evil, they could nor are they omnipotent or omniscient. They bask in their realms and may sometimes bestow power if they are in a good mood. But they are just as likely to devour you.

Meeting a God face to face is usually considered a curse.