Achelous was the god of the greatest river in Greece and the chief of all river-gods — a powerful, shape-shifting deity who fought the hero Heracles for the hand of a princess, lost a horn in the struggle, and so gave the world one of its most enduring symbols: the cornucopia, the horn of plenty.
The Chief of the River-Gods
Achelous was the personification of the Achelous River, the longest in Greece, and as such he was regarded as the eldest and most senior of all the thousands of river-gods (the Potamoi, sons of Oceanus and Tethys). He was a god of fresh water and fertility, depicted as a powerful figure who could take many forms — appearing as a man, as a man-faced bull, or as a great serpent — for like many water-deities, Achelous was a shape-shifter.
The Fight for Deianira
His most famous myth is his wrestling match with Heracles. Both the river-god and the hero sought to marry the beautiful princess Deianira, and they fought a tremendous duel to decide the matter. Achelous used his shape-shifting powers, transforming first into a writhing serpent, then into a charging bull — but Heracles, the supreme wrestler, matched him at every turn. As Achelous charged in bull-form, Heracles seized him by the horns, wrestled him to the ground, and broke off one of his horns, finally defeating him. The river-god, humbled, conceded, and Heracles won Deianira.
The Horn of Plenty
The broken horn became something wonderful. In one tradition, the river-nymphs (Naiads) took Achelous's severed horn and filled it with fruits and flowers, and it became the cornucopia — the “horn of plenty” that overflows endlessly with the bounty of the earth, a symbol of abundance and harvest that endures to this day on coins, in art, and at every celebration of plenty. (In another version, Achelous recovered his own horn by trading the magical horn of Amalthea for it.) From a god's defeat sprang an eternal emblem of abundance.
The Father of Waters
Achelous endures as the grand old man of Greece's rivers, the shape-shifting god of fresh water and fertility, and the unlikely origin of the cornucopia. He represents the life-giving and untameable power of the river — a force even Heracles could only defeat by seizing it by the horns — and from his loss, the world gained its symbol of endless plenty.
Even a god lost a horn to Heracles — and from that broken horn poured the endless bounty of the earth.