Oceanus was the Titan personified as the great river encircling the world.
In Greek cosmology, Oceanus was the eldest son of Uranus, the sky, and Gaia, the earth. Rather than representing the modern ocean alone, he embodied Okeanos, the enormous world-encircling stream believed to mark the outer boundary of the earth. Greek artists often depicted him as a horned, bearded water deity, sometimes with crab-claw features.
Oceanus married his sister Tethys. Hesiod says they became the parents of three thousand river gods and three thousand Oceanids, including such named figures as Achelous, Alpheus, Styx, and Metis. These mythic descendants helped explain rivers, springs, and other bodies of water.
Oceanus is sometimes confused with Poseidon, the Olympian god of the sea, or with Pontus, the primordial personification of the sea. Oceanus was a Titan and cosmic boundary figure, while Poseidon ruled the sea in the Olympian order. Homer also preserves a tradition in which Oceanus and Tethys may have been primeval parents of the gods.