In Greek mythology, Nereus was the eldest son of Pontus (the Sea) and Gaia (the Earth), and a primordial sea-god known as the truthful, gentle "Old Man of the Sea." With the Oceanid Doris he fathered the fifty Nereids — among them Thetis, mother of Achilles, and Amphitrite, consort of Poseidon — as well as a son, Nerites. A shapeshifter gifted with prophecy, he was famed above all for his honesty and his unfailing sense of what is right.
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I.Family
Nereus was the eldest son of Pontus (the Sea) and Gaia (the Earth). With the Oceanid Doris he became the father of fifty daughters, the Nereids, and a son, Nerites, dwelling with them in the Aegean Sea.
Among his daughters were Thetis, a Nereid who became the mother of the great hero Achilles, and Amphitrite, who married Poseidon. The number and names of the Nereids vary across the ancient sources.
II.Name
The name Nereus is absent from Homer's epics. In the Iliad the god is referred to descriptively as the "Old Man of the Sea," while the Odyssey applies that title to both Nereus and Proteus. The same descriptor was used for other water deities, including Phorcys, Glaucus, and possibly Triton. Scholars have suggested that the "Old Man of the Sea" archetype may once have played a cosmogonic role similar to that of Oceanus before receiving different names in different regions.
The name of the Nereids appears in Greek sources, already in the Iliad, before the name of Nereus himself is attested. This has led some to propose that Nereus's name derives from his daughters rather than the reverse.
In Hesiod's Theogony, where the name first appears, Nereus is presented in juxtaposition to Eris. The text employs contrasting verbs and adjectives — "does-not-lie" and "does-not-forget" for Nereus versus "Lies" and "Forgetfulness" for Eris's children — and various etymologies have been proposed for the name (see Etymology).
III.Mythology
In the Iliad, the Old Man of the Sea functions as the father of the Nereids, though Nereus is not directly named. He is characterized as a shapeshifter with prophetic powers who aided heroes such as Heracles when they captured him, despite his transformations. Nereus and Proteus appear as two manifestations of a sea-god subsequently displaced by Poseidon following Zeus's overthrow of Cronus.
Pherekydes of Athens was the earliest poet to connect Nereus with Heracles's labors, according to a scholion on Apollonius of Rhodes. During the fifth century BCE, artistic depictions gradually replaced Nereus with Triton in imagery showing Heracles wrestling a sea-god for information, independent of the literary sources.
In a late appearance documented by fragmentary papyrus, Alexander the Great paused at the Syrian seashore before the Battle of Issus (333 BCE) and prayed, "calling on Thetis, Nereus and the Nereids, nymphs of the sea, and invoking Poseidon the sea-god."
Nereus was renowned for truthfulness and virtue. An ancient quotation describes him: "But Pontos, the great sea, was father of truthful Nereus who tells no lies, eldest of his sons. They call him the Old Gentleman because he is trustworthy, and gentle, and never forgetful of what is right, but the thoughts of his mind are mild and righteous."
IV.Nerites
According to Aelian's natural history, Nereus fathered a watery consort of Aphrodite and lover of Poseidon named Nerites, who was transformed into a small spiral-shelled shellfish of surpassing beauty.
V.In art
Attic vase-painters depicted Nereus as a draped torso emerging from a long, coiling, scaly fishlike tail. Bearded, he typically wielded a staff of authority and appeared in scenes depicting the flight of the Nereids as Peleus wrestled their sister Thetis.
By the fifth century BCE, Triton gradually came to replace Nereus in such depictions of a hero seizing a shapeshifting sea-god for knowledge.