01 · The stories
Myths & defining acts
Draws the sea by lot when the brothers divide the world (Iliad 15); contests Attica with Athena (Apollodorus 3.14.1; Pausanias 1.24.5); helps build Laomedon's walls and is not paid (Apollodorus 2.5.9); in anger at the blinding of Polyphemus, holds Odysseus back from home (Odyssey 1, 9); and in the Aeneid calms the storm that scattered Aeneas's fleet (Aeneid 1.124–156).
02 · Sacred lineage
Family & relations
Parents: Cronus and Rhea. Siblings: Hestia, Demeter, Hera, Hades and Zeus (Hesiod, Theogony 453–458). Consort: Amphitrite, with whom he is the father of Triton (Theogony 930–933). Other children named in the sources: Polyphemus, in the Odyssey (1.68–71); Pegasus and Chrysaor, who spring from Medusa's neck when Perseus cuts off her head (Theogony 278–281); and Orion, in Pherecydes's account (Apollodorus 1.4.3).
Greek literary genealogies and Roman cult identities are not interchangeable. Explore the family tree and its traditions.
03 · Places of devotion
Abode & sacred sites
The sea. In the Iliad he watches the fighting from the topmost crest of Samothrace (13.10–14). His sanctuary on the Isthmus of Corinth was the site of the Isthmian games (Pausanias 2.1.7). In Rome, a temple of Neptune stood on the Campus Martius near the Circus Flaminius, and the Neptunalia was celebrated on 23 July.
04 · Two traditions
Greek & Roman perspectives
The Greek perspective
In the Iliad, Poseidon tells Zeus that the three brothers drew lots for the sea, the underworld and the sky, and that he is of like honour with Zeus (15.185–193). In the Odyssey, he is angry with Odysseus for blinding his son Polyphemus (1.68–71; 9.526–536). Pausanias says the rear pediment of the Parthenon showed the contest between Poseidon and Athena for the land of Attica (1.24.5). Apollodorus says that Poseidon struck the Acropolis with his trident and produced a sea (3.14.1), and that he and Apollo built walls for Laomedon, who then refused to pay them (2.5.9).
The Roman perspective
In Virgil, Neptune hears a storm raging on the sea, lifts his head above the water, sees Aeneas's fleet scattered, and calms the sea (Aeneid 1.124–156). Modern reference works describe the Neptunalia as a festival of Neptune held on 23 July.
05 · Extensive analysis
A closer reading
Hesiod and Homer give Poseidon the sea and the power to shake the earth, and the Odyssey makes him the god whose anger keeps Odysseus from home. Virgil's Neptune is the god who calms a storm. The Isthmian games and the Athenian Acropolis story show his cult in Greece, and the Neptunalia and his temple on the Campus Martius show him at Rome.
06 · Primary sources
What the sources say
These are the main ancient passages behind this entry, with what each one actually says.
- Hesiod, Theogony lines 453–458
Poseidon, called the loud-crashing Earth-Shaker, is one of the six children of Rhea and Cronus, brother of Zeus, Hades, Hera, Demeter and Hestia.
Read the passage - Hesiod, Theogony lines 930–933
Poseidon and Amphitrite are the parents of great, wide-ruling Triton, who owns the depths of the sea.
Read the passage - Homer, Iliad book 15, lines 185–193
Poseidon answers Zeus's threat by saying he is of like honour with him. He says three brothers were born to Rhea and Cronus, and that when the world was divided by lot the sea fell to him, the underworld to Hades and the sky to Zeus.
Read the passage - Pausanias, Description of Greece book 1, chapter 24, section 5
The rear pediment of the Parthenon showed the contest between Athena and Poseidon for the land of Attica.
Read the passage - Virgil, Aeneid book 1, lines 124–156
Neptune hears the storm that has scattered Aeneas's fleet, raises his head above the water, sees the Trojan ships scattered and distressed, and calms the sea.
Read the passage - Hesiod, Theogony lines 278–281
When Perseus cuts off Medusa's head, great Chrysaor and the horse Pegasus spring forth.
Read the passage - Homer, Odyssey book 1, lines 68–71
Poseidon is filled with stubborn wrath because of the Cyclops Polyphemus, whom Odysseus blinded.
Read the passage - Homer, Iliad book 13, lines 10–14
Poseidon has been watching the battle from his seat on the topmost crests of Samothrace.
Read the passage - Pausanias, Description of Greece book 2, chapter 1, section 7
In the sanctuary of Poseidon at the Isthmus stand statues of victors in the Isthmian games, and bronze Tritons stand on the temple.
Read the passage - Apollodorus, Library book 1, chapter 4, section 3
Pherecydes says Orion was a son of Poseidon and Euryale.
Read the passage - Apollodorus, Library book 3, chapter 14, section 1
Poseidon is the first to come to Attica and with a blow of his trident on the Acropolis produces a sea.
Read the passage - Apollodorus, Library book 2, chapter 5, section 9
Apollo and Poseidon, in human form, fortify Pergamum for wages, and Laomedon refuses to pay.
Read the passage - Virgil, Georgics book 1, lines 12–14
Virgil addresses Neptune, at whose trident's stroke the war-horse first sprang from the earth.
Read the passage - Wikipedia, Temple of Neptune (Rome), a modern summary introduction
The temple of Neptune stood on the Campus Martius near the Circus Flaminius in Rome.
Read the passage - Wikipedia, Neptunalia, a modern summary introduction
The Neptunalia was a festival of Neptune as god of waters, held on 23 July.
Read the passage
Where the sources differ
- Homer divides the world by lot among three brothers and gives Poseidon the sea (Iliad 15.187–193), while Virgil's Neptune appears as the god who calms a storm (Aeneid 1.124–156). The two poets use the god for different roles.
07 · Story & deeper insight
Poseidon and the blinding of Polyphemus
Odysseus escapes the Cyclops Polyphemus by blinding him and concealing his companions beneath sheep. The rescue becomes a catastrophe when Odysseus announces his real name from the departing ship. Polyphemus calls on his father Poseidon to punish the man responsible, asking that his return be delayed and, if he returns at all, that he arrive alone and find trouble at home.
The story connects intelligence with its limits. Odysseus's cunning defeats immediate danger, but his desire for recognition exposes him to a power he cannot master. Poseidon's anger makes the sea a space where heroic competence does not guarantee safety. The Cyclops's own brutality also prevents an easy division between just punishment and divine favouritism.
In the Aeneid, however, he can appear as the authority who suppresses an unauthorised storm. Together these scenes show the sea god as both a threat to travellers and the power that restores order to the waters.