That's probably true. It seems to make the most sense.From my reading, animism (the belief that everything is "animated" by spirits) seems to be the oldest.
Primitive peoples tried to identify with the prey by wearing hides and skins or antlers and performing rituals, perhaps to understand the animal in order to better hunt them.
And it's a perfect illustration of why God of the Gaps is such a huge fallacy. We put on deer antlers so we can control the deer or obtain its power. Then we create a god based on the deer. Then a church based on the god. Then we learn what makes a deer tick. We learn about the biology of the deer. We lose interest in the temple, in the god, in wearing antlers. We don't need it anymore. Now we think god resides in the areas where we don't know something, like "prior" to the Big Bang.
God is the sun. The sun is energy, feeding the earth. Ok, then god is the earth. The earth is rock and metal spinning and rotating and traveling around the sun. Ok, god is the motion of the heavenly bodies. The motion is the effect of gravity and certain other physical "laws" that we can predict with a surprising accuracy. Well then god is the unpredictable nature of quantum physics...
God's place gets smaller and smaller. God of the Gaps. Makes much more sense to simply accept that there isn't any evidence to have a belief in god. Atheism is that position.