Hesiod is the earliest Greek poet who says anything concrete about himself. He names his father as an emigrant from Aeolian Kyme who settled at Askra in Boiotia, describes the place unflatteringly, mentions a lawsuit with his brother Perses over their inheritance, and records winning a tripod for a song at a funeral contest in Chalkis. Whether these details are autobiography or a persona is debated, but they are far more than Homer's poems give.
The date is usually put around 700 BCE, close to Homer and possibly slightly later, though the relative order of the two has never been settled. The poems were composed within an oral tradition of hexameter verse, sharing its formulaic diction and its stock epithets, and were fixed in writing at some point in the same period that Greek adopted the alphabet.
Hesiod's other surviving poem, Works and Days, is its companion in the sense that it applies the same theology to daily life: a farmer's calendar wrapped around a moral argument that Zeus rewards justice and punishes the crooked verdict, containing the Prometheus and Pandora story and the sequence of declining ages of humanity. Read together, the two set out a cosmos in which power was won by force and is now exercised, on the whole, lawfully. Several further works circulated under Hesiod's name in antiquity, including the Catalogue of Women, which survives only in fragments and which most scholars judge later than the Theogony.
The Theogony's own ending is unstable. The closing lines shade into the opening of the Catalogue, and most editors treat the last hundred or so verses as expanded by later hands, which is a reminder that an oral-derived poem had no fixed edge. The text reached the medieval manuscripts through the same Byzantine copying that preserved Homer, and Hesiod was read in schools alongside him throughout antiquity.