Greek Gods

How it all started.

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In Greek mythology, there was nothing but Chaos in the beginning: Chaos was autogenic. Chaos is called an elemental force, which is force made of itself alone and not composed of anything else. It exists from the beginning of the universe. To coin a phrase, you could say, "in the beginning, there was Chaos." Period.

The idea of having the principle of Chaos at the beginning of the universe is like the New Testament idea that in the beginning was "The Word".

Out of Chaos spun out other elemental forces or principles, like Love, Earth, and Sky, and in a later generation, the Titans
The first few generations were progressively more like humans: The Titans were the children of Gaia (Ge 'Earth') and Uranus (Ouranos 'Sky') -- the Earth and Sky. The Olympian gods and goddesses were children born later to one specific pair of Titans, making the Olympian gods and goddesses grandchildren of Earth and Sky.

The Titans and the Olympians inevitably came into conflict. Since you have probably heard a lot about the Olympian gods and little about the Titans, you can guess who won, but before you go writing off the Titans as an irrelevant footnote to Greek mythology, the giant holding the world on his shoulders, Atlas, is a Titan.
(Some of the credit goes to: http://ancienthistory.about.com/od/myths/a/GreekMythology.htm)

Family Tree of the Greek Gods

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