Many Oceanids including: In Greek mythology, Oceanus (/oʊˈsiːənəs/ oh-SEE-ə-nəs;[1] Ancient Greek: Ὠκεανός[2] [ɔːke.anós], also Ὠγενός [ɔːɡenós], Ὤγενος [ɔ̌ːɡenos], or Ὠγήν [ɔːɡɛ̌ːn])[3] 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.

[11] Hesiod lists his Titan siblings as Coeus, Crius, Hyperion, Iapetus, Theia, Rhea, Themis, Mnemosyne, Phoebe, Tethys, and Cronus.

[14] These included: Achelous, the god of the Achelous River, the largest river in Greece, who gave his daughter in marriage to Alcmaeon[15] and was defeated by Heracles in a wrestling contest for the right to marry Deianira;[16] Alpheus, who fell in love with the nymph Arethusa and pursued her to Syracuse where she was transformed into a spring by Artemis;[17] and Scamander who fought on the side of the Trojans during the Trojan War and got offended when Achilles polluted his waters with a large number of Trojan corpses, overflowed his banks nearly drowning Achilles.

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.

"[40] However, as Timothy Gantz points out, "mother" could simply refer to the fact that Tethys was Hera's foster mother for a time, as Hera tells us in the lines immediately following, while the reference to Oceanus as the genesis of the gods "might be simply a formulaic epithet indicating the numberless rivers and springs descended from Okeanos" (compare with Iliad 21.195–197).

[49] Proclus, in his commentary on Plato's Timaeus, quotes several lines of a poem (probably Orphic) which has an angry Oceanus brooding aloud as to whether he should join Cronus and the other Titans in the attack on Uranus.

[63] Both Hesiod and Homer call Oceanus "backflowing" (ἀψορρόου), since, as the great stream encircles the earth, it flows back into itself.

[69] Both Hesiod and Homer locate Oceanus at the ends of the earth, near Tartarus, in the Theogony,[70] or near Elysium, in the Iliad,[71] and in the Odyssey, has to be crossed in order to reach the "dank house of Hades".

[73] The Theogony has such fabulous creatures as the Hesperides, with their golden apples, the three-headed giant Geryon, and the snake-haired Gorgons, all residing "beyond glorious Ocean".

[87] Oceanus is represented, identified by inscription, as part of an illustration of the wedding of Peleus and Thetis on the early sixth century BC Attic black-figure "Erskine" dinos by Sophilos (British Museum 1971.111–1.1).

Oceanus also appears, as part of a very similar procession of Peleus and Thetis' wedding guests, on another early sixth century BC Attic black-figure pot, the François Vase (Florence 4209).

[91] As in Sophilos' dinos, Oceanus appears at the end of the long procession, following after the last chariot, with Hephaestus on his mule bringing up the rear.

[93] Oceanus is depicted (labeled) as one of the gods fighting the Giants in the Gigantomachy frieze of the second century BC Pergamon Altar.

Speaking about the Oceanus myth itself he declared: As for the writer who attributes the phenomenon to the ocean, his account is involved in such obscurity that it is impossible to disprove it by argument.

[citation needed] Late attestations for an equation with the Black Sea abound, the cause being – as it appears – Odysseus' travel to the Cimmerians whose fatherland, lying beyond the Oceanus, is described as a country divested from sunlight.

[101] Hecataeus of Abdera also refers to a holy island, sacred to the Pelasgian (and later, Greek) Apollo, situated in the westernmost part of the Okeanós Potamós, and called in different times Leuke or Leukos, Alba, Fidonisi or Isle of Snakes.

It was on Leuke, in one version of his legend, that the hero Achilles, in a hilly tumulus, was buried (which is erroneously connected to the modern town of Kiliya, at the Danube delta).

Accion ("ocean"), in the fourth century AD Gaulish Latin of Avienius' Ora maritima, was applied to great lakes.