“First of all Chaos came to be.”
Theogony
Hesiod presents himself as a shepherd of Boeotia who was called by the Muses to sing. His Theogony is the closest thing Greek religion has to a systematic account of the gods: the emergence of Chaos, Gaia and Uranus, the castration of Uranus, the Titanomachy, and the reign of Zeus.
In Works and Days he shifts to ethics and farming, weaving in the myth of Pandora and the ages of humankind. Together the poems show myth being used to explain labour, justice and the human condition.
Legacy
Alongside Homer, Hesiod shaped what later Greeks meant by 'the gods', and his genealogy underpins nearly every later telling.