Many people know bits and pieces of the story of the Olympian gods and their rise to power but not always from beginning to end. So here we go:
Before the Olympian gods had come into power, the Titans ruled the world. There were twelve original titans from the marriage of Gaia (Earth) and Uranus (sky). Cronus (Kronus) and Rhea ruled over the titans after overthrowing their father Uranus. Cronus was paranoid that his son would overthrow him so he ate all of his children. His first five children were devoured quickly after Rhea birthed them, these were Hestia, Demeter, Hera, Poseidon, and Hades. When Rhea discovered she was pregnant with her sixth child, Zeus, she became stricken with grief, knowing this child was destined for the same fate as his five older siblings.
Rhea hid the child on the Island of Crete and tricked Cronos to eat a stone wrapped in swaddling clothes. Zeus grew up in secret on the island until he was old enough to confront his father. He snuck into his palace as a cupbearer and tricked him into drinking a potion that would force him to spit up his children. All five children came out of Cronus, fully grown.
Thus began the war of the titans against the Olympians, known as the Titanomachy. The six Olympians, led by Zeus, and the twelve titans, led by Cronus and Atlas, waged war for years. Zeus finally gained the upper hand with some unlikely allies, the titans Prometheus, blessed with the power of foresight, and his brother Epimetheus, sided with the Olympians because Prometheus foresaw the victory of the Olympians. Zeus also went to Tartarus, the deepest pit in the underworld, and freed the oldest children of Uranus and Gaia: the three Cyclopes and three Hecatonchires (giant monsters with 100 arms and 50 heads!). Zeus promised to free them if they were to fight against their titan siblings. The Cyclopes forged Zeus’ lightning bolt, Poseidon’s Trident, and Hades’ helm of invisibility while the Hecatonchires threw massive boulders at the titans continually until they were defeated.
The Olympians were then victorious, banishing the titans to Tartaurus (with the exception of Atlas who was punished to hold up the sky) and guarded by the Hecatonchires. The birth of the other 6 Olympians would be another blog entirely!