Argonauts, a name given from that of their ship, the Argo, to a band of heroes of Greek antiquity, who, according to the legend, first navigated unknown and dangerous seas. The poets have given different versions of the tradition, but the story generally accepted is briefly as follows. Jason, the son of Aeson, was ordered by his uncle Pelias, king of lolcus in Thessaly (who had been warned by the oracle to dread his nephew), to capture and bring to him the golden fleece of the ram which had carried Phrixus and Helle when they fled from their stepmother Ino. Phrixus had nailed the fleece to an oak in the grove of Mars in Colchis, where it was watched by a sleepless dragon. Joined by the principal heroes of Greece, whom he had invited to take part in the adventure, Jason set sail from Iolcus in the fifty-oared ship Argo, named from Argos, son of Phrixus, who had built it for the expedition. The heroes landed first in Lemnos, where the Lemnian women, who on account of the anger of Venus had slain their husbands, detained them two years. The Doliones, whom they next visited, at first received them hospitably, but afterward, mistaking them for Pelasgians, attacked them; and Jason in the battle killed their prince.

In Mysia, their next landing place, Hylas, led away by a nymph, and Hercules and Polyphemus, who were searching for him, were left behind. In the land of the Bebryces King Amycus, who had challenged the heroes to a boxing match, was slain by Pollux. Continuing their voyage, they reached the Symplegades, two floating islands which crushed, in dashing against one another, whatever came in their way. Availing themselves of an artifice taught them by the seer Phineus and Juno, who acted as their pilot, they let loose a dove, only the tail of which was crushed by the colliding rocks, and the Argonauts passed safely between as the islands rebounded. The islands from this time ceased their dangerous movements. Reaching Colchis at last, the heroes sought the king, Aeetes, who promised the fleece to Jason on condition that he should yoke to the plough two tire-breathing bulls, and sow the dragon's teeth left by Cadmus in Thebes. Aided by the daughter of .Aeetes, Medea, a powerful enchantress, who had fallen deeply in love with him, Jason accomplished these tasks; but finding Aeetes plotting treachery, the hero, again assisted by Medea's enchantments, seized the fleece, carried it on board his ship, and set sail, accompanied by Medea and her brother Absyrtus. Pursued by Aeetes, Medea killed Absyrtus, and, throwing his body piece by piece into the sea, delayed the king, who stopped to gather the remains of his son, while the Argonauts escaped.

But the mast of the Argo, which was made of Do-donian oak having the gift of prophecy, told the heroes that for the crime against Absyrtus they were condemned to undergo innumerable difficulties on their homeward voyage. Having been absolved by the enchantress Circe, they escaped Scylla and Charybdis with the help of Thetis, eluded with the aid of Orpheus the enticements of the sirens, and after four months of continued danger reached Iolcus. The Argo was consecrated by Jason on the isthmus of Corinth to Neptune.