The beginning in Greek mythology is quite complex and there are several different versions. However, the most well-known version is the one told in Hesiod's "Theogony." According to Hesiod, in the beginning, there was only chaos. From this chaos, the first gods emerged: Gaia (the Earth), Tartarus (the underworld), and Eros (love). These three gods then gave birth to other gods and goddesses, including Uranus (the sky) and Pontus (the sea).
Gaia and Uranus became the parents of the Titans, Cyclopes and the Hecatonchires. Uranus was the father of the Titans, the Cyclops and the Hecatonchires, but he was a cruel father, so Gaia asked her children to help her get rid of him. The Titans Cronus, the youngest and most ambitious, castrated Uranus and became the ruler of the universe, but he also was a cruel ruler, so his son Zeus would eventually overthrow him and become the ruler of the Olympians.
Zeus, Poseidon and Hades, the three sons of Cronus, overthrew the Titans and became the new rulers of the universe. They drew lots to determine who would rule the sky, the sea, and the underworld. Zeus became the ruler of the sky and the king of the gods, Poseidon became the ruler of the sea, and Hades became the ruler of the underworld. The Olympian gods then created the world and all the living creatures in it. They also created humans, who were initially immortal but later were punished to live mortal lives. They also created many monsters and creatures such as centaurs, minotaurs and gorgons. The gods lived on Mount Olympus and interacted with humans, often intervening in their affairs and punishing those who angered them.
This is the basic narrative of the Greek creation myth, but there are many variations and additional stories within it. The creation myth is an important foundation for the rest of Greek mythology, as it sets the stage for the actions and interactions of the gods and goddesses.
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