Answer:
In Ancient Greek mythology, twelve gods and goddesses ruled the universe from atop Greece's Mount Olympus. Our main sources on the gods include Hesiod's Theogony and the Homeric Hymns (although they probably aren't by the Homer who wrote the Odyssey).
These Olympians had come to power after their leader, Zeus, overthrew his father,Kronos(or Cronus), leader of the Titans. All the Olympians are related to one another. The Romans adopted most of these Greek gods and goddesses, but with new names. There were many more deities in the Roman and Greek pantheons. We've included some of the more prominent deities below, in addition to the main Olympians. You can find a more complete list of Greco-Roman deities here.