In Greek mythology, Oceanus was a Titan son of Uranus and Gaia, the husband of his sister the Titan Tethys, and the father of the river gods and the Oceanids, as well as being the great river which encircled the entire world.
Passages in a section of the Iliad called the Deception of Zeus, suggest the possibility that Homer knew a tradition in which Oceanus and Tethys (rather than Uranus and Gaia, as in Hesiod) were the primeval parents of the gods.Although sometimes treated as a person (such as Oceanus visiting Prometheus in Aeschylus’ Prometheus Bound, see above) Oceanus is more usually considered to be a place, that is, as the great world-encircling river.Homer says that Oceanus “bounds the Earth”, and Oceanus was depicted on the shield of Achilles, encircling its rim, and so also on the shield of Heracles.And for both Hesiod and Homer, Oceanus seems to have marked a boundary beyond which the cosmos became more fantastical.In Homer, Helios the sun, rises from Oceanus in the east, and at the end of the day sinks back into Oceanus in the west, and the stars bathe in the “stream of Ocean”.The concept of the surrounding Ocean, as expressed by Homer and Hesiod, remained in common use throughout antiquity.