Greek people have common beliefs.
Ancient Greek theology was based on polytheism. The assumption is there were many gods and goddesses. Zeus, the king of the gods, having a level of control over all the others, but he was not omnipotent. Some gods or goddesses have already have power of controlling aspects of the nature, for instance, Zeus was the sky-god, sending thunder and lightning, Poseidon ruled over the sea and earthquakes, and Helios ruled over the sun. Other deities ruled over an abstract concept, for instance Aphrodite controlled love.
Family tree of the Greek Gods:
