Poseidon

Poseidon, in ancient Greek religion, god of the sea (and of water generally), earthquakes, and horses. He is distinguished from Pontus, the personification of the sea and the oldest Greek divinity of the waters. The name Poseidon means either “husband of the earth” or “lord of the earth.” In the Greek pantheon he was one of the 12 Olympians and the most powerful after his brother Zeus, the sky god and chief deity of ancient Greece. Unlike most of the other gods, who lived on Mount Olympus, Poseidon lived under the sea. His weapon and main symbol was the trident, perhaps once a fish spear. According to the Greek poet Hesiod, Poseidon’s trident, like Zeus’s thunderbolt and Hades’ helmet, was fashioned by the three Cyclopes. His character as a sea god eventually became his most prominent in art. He was often portrayed in a chariot drawn by hippocampi (mythical horse-like sea creatures) and accompanied by dolphins and other marine life. The Romans, ignoring his other aspects, identified him with Neptune as sea god.

Birth and relationship with Zeus

Traditionally, Poseidon was a son of Cronus (the youngest of the 12 Titans) and of Cronus’s sister and consort Rhea, a fertility goddess. Along with his brother Hades and sisters, Hestia, Demeter, and Hera, Poseidon was swallowed by Cronus, who was destined to be overthrown by one of his children. Poseidon and his siblings were liberated with the help of Zeus, who had been hidden from Cronus by Rhea. In one version Poseidon too was hidden at birth by Rhea, who gave Cronus a foal to swallow instead.

Zeus, Poseidon, and Hades deposed their father, and the kingdom of the sea fell by lot to Poseidon while the sky went to Zeus and the underworld to Hades. However, the gods were often at odds. Poseidon conspired with Hera and Apollo to challenge Zeus’s supremacy. When the attempted coup failed, Zeus suspended Hera from the sky and sentenced Poseidon and Apollo to a year of service to a mortal. They were hired to build the walls of Troy by King Laomedon, who then refused to pay them at the end of the year. Enraged, Poseidon sent a sea monster and Apollo a plague to ravage Troy. Years later Poseidon favored the Greeks in the Trojan War by rallying their forces and sometimes attempting to directly influence the outcome of the war.

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From Athena to Zeus: Basics of Greek Mythology

Disagreements with other gods

Poseidon came into conflict with a variety of figures in land disputes. Notable among these was a contest for sovereignty over Attica, which he lost to the goddess Athena. The mortals preferred her gift—the first olive tree—to that of Poseidon’s—a spring of salt water—and the city of Athens thus received its name. In some versions Poseidon’s gift was the first horse. Despite losing, Poseidon was also worshipped in Attica, particularly at Colonus (as hippios, “of horses”). He also lost dominance over Argos to Hera. Poseidon flooded Attica and Argos after losing the contests. When both Poseidon and the sun god, Helios, claimed the city of Corinth, Poseidon was awarded the isthmus while Helios received the acropolis.

Role in the Odyssey

In Homer’s Odyssey the hero, Odysseus, earned Poseidon’s enmity during his voyage home to Ithaca after the Trojan War. In their third stop Odysseus and some of his companions were captured by Poseidon’s son, the Cyclops Polyphemus, who devoured six of Odysseus’s men and imprisoned the rest in his cave. The crafty Odysseus devised a clever escape by getting Polyphemus drunk, blinding him as he slept, and clinging to the underbellies of Polyphemus’s sheep when he let them out to pasture. Polyphemus prayed to his father for revenge. In answer Poseidon delayed Odysseus’s homecoming by 10 years, causing shipwrecks and other disasters. Odysseus alone survived the journey to Ithaca.

Odysseus learned of Poseidon’s antagonism from the spirit of the seer Tiresias, whom he descended into the underworld to consult. Tiresias also revealed how Poseidon could be appeased—after reaching Ithaca and recovering his throne, Odysseus would have to travel inland to northern Greece with an oar; when he reached a place where people knew nothing of the sea, had never seen an oar, and mistook it for a winnowing fan, he would have to plant it in the ground. Post-Homeric accounts relate that Odysseus did as Tiresias specified and completed his expiation with a sacrifice to Poseidon.

Consorts and children

In amorous matters Poseidon was often aggressive, as in his pursuits of the goddess Demeter and the Gorgon Medusa, and his offspring were myriad. He wooed Demeter when she was grieving her daughter, Persephone, who had been abducted by Hades. Demeter transformed herself into a horse but was unable to evade Poseidon, who took the form of a stallion. Two children were born from their union—Arion, an immortal and extraordinarily swift horse, and Despoine, or Despoena, worshipped as a fertility goddess. Poseidon assaulted Medusa (in some stories the union was consensual) in a temple to Athena, causing the angry Athena to transform Medusa from a beautiful woman into a snake-haired monster. Medusa conceived two of Poseidon’s offspring—the winged horse Pegasus and the warrior Chrysaor, who were released from the blood that spilled when she was slain by Perseus.

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Poseidon was the father of Pelias and Neleus by Tyro, the daughter of Salmoneus, and thus became the divine ancestor of the royal families of Thessaly and Messenia. Many of his sons became rulers in other parts of the ancient Greek world. In some accounts he is regarded as the father of the hero Theseus, who became famous for slaying the Minotaur. He also had many monstrous offspring, including giants and savage creatures, such as Orion, Antaeus, and Polyphemus. Progenitor of many, with several consorts, Poseidon was married to the Oceanid Amphitrite, with whom he also had multiple offspring, including the sea creature Triton.

God of horses and earthquakes

In some stories Poseidon created the horse, along with the hippopotamus, the zebra, the donkey, and the camel, to win Demeter’s favor. In some traditions his gift of the horse finally won Demeter over. As the god of horses, Poseidon is thought likely to have been introduced to Greece by the earliest Hellenes, who also introduced the first horses to the country about the 2nd century bce. Poseidon himself fathered many horses, best known of which was Pegasus.

Poseidon created several sea creatures, such as the dolphin for Amphitrite. Poseidon was also associated with bulls and sent one from the sea to the Cretan king Minos who had promised to sacrifice it to the god. However, Minos kept the magnificent bull for himself and sacrificed a different one. Poseidon retaliated by causing Minos’s wife, Pasiphae, to lust for the bull, and the resulting union produced the monstrous Minotaur.

As the god of earthquakes, Poseidon was also connected to dry land, and many of his oldest places of worship in Greece were inland, though these were sometimes centered on pools and streams or otherwise associated with water. In this aspect, he was known as enosichthōn and ennosigaios (“earth-shaker”) and was worshipped as asphalios (“stabilizer”). The chief festival in Poseidon’s honor was the Isthmia, the scene of famous athletic contests (including horse races), celebrated in alternate years near the Isthmus of Corinth.