At first, there was just Chaos (an empty void). From Chaos sprung Gaia (Earth), Eros (Love), Tartarus (Dungeon of Torture) and Erebus (Darkness). Along with them came Nyx (Night), one of the most powerful primordial beings (Even Zeus was afraid of her). Erebus and Nyx had a kid named Hemera (Day) who bought light into the world of darkness. Gaia gave birth to Uranus (Sky) with whom she produced 12 sons and 6 daughters. They came to be known as the Titans. Uranus disliked some of his kids so he tossed them in Tartarus. This upset Gaia so she asked her son Cronus to end Uranus's reign. She gave Cronus an indestructible sickle (with whom he is often depicted in art). Cronus would go on to slice his father's genitals and become the ruler of the world.

Cronus married his sister Rhea and had 6 sons and 3 daughters. His parents, Gaia (Earth) and Uranus (Sky) prophesied that one of his kids will overpower Cronus and rule the world. To prevent this from happening, Cronus ate his kids as they were born. Rhea was unhappy that all her kids were helplessly eaten so she decided to save her youngest son Zeus. She dressed a rock in infant clothing and gave it to Cronus to eat. She then gave Zeus to his grandmother Gaia to raise him. After Zeus reached manhood, he secretly gave Cronus an emetic drink which made him puke his kids out. Hades, Hera, Poseidon, Demeter and Hestia were ready to battle against the Titans. So the Battle of the Titanomachy pursued for 10 long years. At the end, the Gods - Zeus and his siblings won the war. From Tartarus, the Gods released the 100-handed Giants, the Cyclopes and legendary craftsmen, would force Zeus - a mighty thunderbolt, Poseidon - a Trident and Hades - a hat of invisibility.

After the defeat of the Titans, the gods ruled the world. It was decided that each realm would be ruled by each brother- Zeus (Sky), Poseidon (Sea), and Hades (Underworld). The Gods resided on Mount Olympus, earning the name 

"The 12 Olympians"

They consisted of - Zeus (Sky), Poseidon (Sea), Hera (Marriage), Demeter (Fertility), Aphrodite (Beauty), Athena (War and Knowledge), Artemis (Huntress), Apollo (Healer and Music), Ares (war), Hephaestus (Fire and Metal), Hermes (Messenger), and Dionysus (Wine). 

At first, there were just monsters and beasts on Earth. Prometheus (foresight) was entrusted with creating animals, together with his brother Epimetheus (hindsight). Some animals received the gift of poison, and others were given the capacity to fly. By the time Prometheus came to create man, he had exhausted his gifts. He created humans out of mud, sculpting in the image of the gods.