According to the Greeks, the world began with them.
After Lycaaon angered Zeus, Zeus flooded the world and only Deucalion and Phyrra were left. Phyrra was told by an oracle of Apollo to take up the bones (rocks) of her mother (Earth) and cast them behind her. She did this and from the stones grew mankind.
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One day Io was spotted by Zeus and raped. Hera appeared and, so he would not be suspected, he transformed her into a cow and gave her to his wife. Hera, the fool that she is not, took Io and gave her to Argus to guard. Zeus, realizing what Hera had done, sent his son Hermes to rescue her. After dispatching Argus, Hermes took her, but unfortunately it was not the end of Io's suffering. Hera sent a gadfly to torture poor Io during her years of wondering.
When Zeus finally took pity on Io and returned her to her human form, she gave birth to sons in (I think) Egypt first, then many other countries, thus spreading Greek blood around the world.