Achelous was an important river god, one of the three thousand Potamoi (“Rivers”) born from the union of Oceanus and Tethys. The name “Achelous” was shared by both the god and the river itself; the mighty Achelous River was the largest river in Greece, flowing from the Pindus Mountains in Epirus into the Ionian Sea.
The god Achelous was also extremely powerful. He featured in a few heroic myths, including one in which he fought Heracles for the hand of the beautiful Deianira. Though Achelous faced his foe in the form of a raging bull, Heracles managed to tear off Achelous’ horn, thus winning the contest.
In ancient art and literature, Achelous was usually imagined as a roaring bull or a man-bull hybrid; in many traditions, the horn he lost to Heracles became the original cornucopia (“horn of plenty”). Achelous was seen as an important god of water and rivers, worshipped widely throughout Greece.
The etymology of the name “Achelous” (Greek Ἀχελῷος, translit. Achelô(i)os) is unclear. Some recent scholars have suggested that the name is of Semitic origin, with the first element ἀχ- (ach-) coming from the Akkadian aḫu (“river bank”) and the second element -ελῷος (-elô(i)os) coming from the Akkadian illu (“watercourse”).
The Etruscan name for Achelous was Αχλαε (Achlae).
Achelous Ἀχελῷος (Achelô(i)os)
Functions and Characteristics
Achelous was the name of both a river and a god. The Achelous River was the largest river in Greece; it rose in Epirus in northwestern Greece, wound through the Pindus Mountains, and finally flowed into the sea near the northeastern entrance to the Corinthian Gulf. This river, characterized by heavy alluvial deposits as it moved south, formed the boundary between Acarnania and Aetolia.
The god of the river was viewed as extremely important and powerful in ancient Greece. Homer described Achelous as the god “from whom all rivers flow and every sea, and all the springs and deep wells”—a god who feared no one but Zeus. In other words, Achelous was more than just the god of a single river (however impressive that river was): he functioned as a god of all fresh water and the fertility of the land.
There were actually several smaller rivers that also bore the name of Achelous. Indeed, the name was sometimes used as a synonym for “water” in general.
Achelous was typically imagined as an imposing figure. Like many other sea gods, he had the ability to change his shape. Thus, when he came to seek the hand of the princess Deianira, he appeared to her in different forms,
coming now as a bull in visible form, now as a serpent, sheeny and coiled, now ox-faced with human trunk, while from his thick-shaded beard wellheads of fountain-water sprayed.
Achelous would later use this shape-shifting ability in his fight with Heracles, though he was still overpowered in the end.
Achelous was often seen in the company of nymphs, many of whom were described as his daughters. These nymphs would dance joyously around the powerful god. Achelous was also associated with the cornucopia (the “horn of plenty”). This was either a gift from the nymph Amalthea or a horn from his own body, which the Naiads filled with fruits after Heracles tore it from his head in a fight.
Achelous was popular in ancient art from as early as the late sixth century BCE, especially in vase paintings. He was most often represented as an animalistic figure, usually as a bull or a man with bull features; sometimes he was a bull with a man’s head, while other times he looked almost like a Centaur.
Achelous was often shown individually, but he was also frequently depicted fighting Heracles. Many of these battle scenes had Heracles gripping or breaking off Achelous’ horn, mimicking literary accounts of the battle.
Achelous also appeared in sculpture, masks, and coinage. He was especially popular on coins from Magna Graecia and Sicily, where he assumed the form of a bull with the head of an old man. Achelous was also represented on the famous Amyclae Throne, an important artifact known today only from ancient descriptions.
Other notable representations of the god include a cedar statue group in the Megarian Treasury at Delphi, which showed him with Ares. Achelous was also important in the art of the Etruscans, who held the god in very high regard.
Achelous was a son of the Titans Oceanus and Tethys, one of three thousand sons known as the Potamoi, or “Rivers.” One early author called him the eldest of the Potamoi. His sisters were the three thousand nymphs known as the Oceanids. In a less common tradition, however, Achelous was described as a child of the earth goddess Gaia.
Achelous had many children with various consorts. He was usually called the father of the Sirens, though sources varied widely concerning the identity of the mother. Most said that the Sirens’ mother was one of the Muses—either Terpsichore (the Muse of dancing), Melpomene (the Muse of tragedy), or Calliope (the Muse of epic). But another tradition claimed that the mother of the Sirens was a mortal woman named Sterope, the daughter of the Calydonian king Porthaon.
Achelous was also the father of Callirhoe, who became the wife of the hero Alcmaeon. With Perimede, he fathered two sons named Orestes and Hippodamas. He was sometimes called the father of the nymphs or of the “Achelesian” nymphs; others referred to Achelous’ nymph daughters as the “Acheloides.”
Some of Achelous’ daughters became affiliated with bodies of water: Achelous was thus the father of Pirene (the namesake of a fountain in Corinth), Castalia (a spring in Delphi), and Dirce (a river in Thebes). Achelous also fathered a certain Eurymedusa, one of Zeus’ countless lovers and the mother of Myrmidon.
Achelous's origins are rather obscure. The god himself was clearly very ancient and important, as demonstrated by the language used to describe him in the Iliad: here, in the earliest surviving Greek text, Achelous is the source and ruler of all water, a being who fears no god but Zeus.
This passage has been interpreted by some scholars as an indication that Achelous was the original water god of Greek mythology, predating even Oceanus (who was Achelous’ father in what eventually became the standard tradition).
The antiquity of Achelous is supported by the fact that man-faced bull gods were often associated with water in ancient Europe. Thus, Achelous may have reached Greece from the Northwest, perhaps passing through Italy. Indeed, we find that Achelous was worshipped as an important god by the Etruscans of northern Italy (which would be surprising if Achelous was merely the god of a single river in Greece rather than a prominent water god).
The ancients had their own ideas about where Achelous—and his river—came from. According to a story reported by the Roman commentator Servius, Achelous was a son of Gaia rather than Oceanus. When he lost his daughters, the Sirens, he called out to his mother in grief. Gaia embraced her son and folded him into her bosom, and the powerful Achelous River burst forth from that spot.
In another story, the river was originally called Thestius, named after a son of Ares and Pisidice who leapt into the river when he discovered that he had accidentally killed his son Calydon. It was renamed Achelous in honor of another jumper, this one a son of Oceanus, who leapt into the river when he learned that he had accidentally slept with his daughter Cletoria.
Meanwhile, the geographer Strabo took a more rationalized approach to the myth of Achelous. According to Strabo, the river was originally called Thoas, “Swift.” Over time, the idea of a god named Achelous arose from the features of the river: Achelous’ bull form was inspired by the roaring of the river’s water; his snake form was inspired by the river’s twisting and its length; and so on.
Achelous and Heracles
Probably the most important myth of Achelous tells of how the god wrestled the hero Heracles for the hand of the beautiful princess Deianira. Achelous transformed himself into all manner of different shapes in his attempt to beat Heracles.
At last, he turned into a bull, but Heracles grabbed him by the horns and wrestled him to the ground, tearing off one of his horns in the process. There may have even been a tradition in which Ares, the god of war, came to Achelous’ aid; but Heracles still prevailed in the end.
Heracles, victorious, married Deinaira, while Achelous skulked away, now missing one of his horns. In some traditions, he was able to trade the inexhaustible cornucopia, or “horn of plenty,” for the horn that Heracles had taken from him. But in other traditions, Heracles refused to return the horn to the humiliated river god, instead presenting it to his new father-in-law as a wedding present.
Some early authors sought a rationalized version of this fantastical myth. The historian Diodorus of Sicily, for instance, suggested that the myth emerged after Heracles diverted the Achelous River—a formidable task. Similarly, the geographer Strabo posited that Heracles dammed the river and created an irrigation system for King Oeneus of Calydon in order to win the hand of his daughter Deianira.
Achelous and Alcmaeon
The god Achelous was also involved in the myth of Alcmaeon, an Argive hero who murdered his own mother when he found out that she was responsible for the downfall of his father. For this terrible crime, Alcmaeon was pursued by the Erinyes, the avenging “Furies.” He was eventually purified by the Arcadian king Phegeus, who gave him his daughter in marriage.
Unfortunately, the ritual didn’t stick: Alcmaeon either became ill or, alternatively, Phegeus’ land became infertile, signs that the gods were still angry with Alcmaeon.
In the popular tradition, Alcmaeon sought the advice of an oracle and was commanded (confusingly) to resettle in a land that had not existed at the time that he killed his mother. Alcmaeon roamed western Greece until he found a delta that had just formed at the mouth of the Achelous River—in other words, a land that had not yet emerged at the moment of his mother’s murder.
There, Alcmaeon was purified by the god Achelous, built a city, and married Achelous’ daughter Callirhoe. Together they had two sons, named Acarnon and Amphoterus.
But Alcmaeon’s fortunes took a turn for the worse when his new wife, Callirhoe, demanded that he give her the infamous robe and necklace of Harmonia, important heirlooms that he had inherited. Unfortunately, Alcmaeon had already gifted these items to his previous wife, the daughter of Phegeus.
At Callirhoe’s insistence, Alcmaeon went back to Arcadia to retrieve the requested heirlooms. But when his reasons for returning to Arcadia were discovered, Alcmaeon was ambushed and killed by his former father-in-law and brothers-in-law.
The violence did not end there. Callirhoe, discovering what had happened to her husband, prayed for her sons to be fully grown so they could avenge their father’s death. The gods answered Callirhoe’s prayers: Acarnan and Amphoterus instantly became adult men and promptly executed Alcmaeon’s murderers. They then dedicated the fateful necklace and robe of Harmonia at Delphi, following the instructions of their grandfather Achelous.
Two further myths involving Achelous can be found in Ovid’s Metamorphoses. In the first of these myths, Achelous tells the heroes Theseus and Pirithous how the Echinades Islands, off the western coast of Greece, were originally five nymphs. One day, these nymphs offered sacrifices to the gods on the banks of the Achelous, but they forgot to sacrifice to Achelous himself. Achelous flew into a rage, overflowed his banks, and swept the nymphs into the sea, where they became the islands known as the Echinades.
The second myth tells of how Achelous took the virginity of a local girl named Perimele. When Perimele’s father, Hippodamas, found out about the affair, he threw his daughter from a cliff into the sea. Witnessing this, Achelous invoked the great sea god Poseidon, asking him to save the poor girl. Poseidon answered Achelous’ prayer and turned Perimele into an island.
Achelous was worshipped extensively throughout the ancient world, in both Greece and beyond. His cult was especially important in western Greece. Every prophecy delivered at the sanctuary of Dodona, for instance, apparently concluded with a command to offer sacrifices to Achelous. In Acarnania, bordered on the east by the Achelous River, the god was honored with regular contests.
There were cults to Achelous in many other parts of Greece, too. As early as the second half of the sixth century BCE, the tyrant Theagenes erected an altar to Achelous in Megara, an important city in eastern Greece (though nowhere near the river itself).
There is also evidence that Achelous was honored in Athens, Marathon, Phaleron, Oropus, Mantinea, Cyme, Didymoi, Sicily, and Rhodes, among other locations. Achelous was worshipped as an important deity even as far afield as Etruria in northern Italy, where he often figured in art.
The worship and rites of Achelous were often conducted in temples or on altars, as was common for all Greek deities. But offerings to the god could also be thrown directly into the water. Thus, on the Aegean island of Mykonos, lambs sacrificed to Achelous were sometimes thrown into a little stream (also called the Achelous).
Such extensive evidence of Achelous’ worship indicates that he was an important river god—perhaps the most important of all the Greek river gods—from an early period. But his influence began to wane by the end of the fourth century BCE, and he was gradually relegated to the status of a minor water god.