(Ποσειδῶν), the god of the Mediterranean sea. His name seems to be connected with πότος, πόντος and ποταμός, according to which he is the god of the fluid element. (Müller, Proleg. p. 290.) He was a son of Cronos and Rhea (whence he is called Κρόνιος and by Latin poets Saturnius, Pind. O. 6.48; Verg. A. 5.799.) He was accordingly a brother of Zeus, Hades, Hera, Hestia and Demeter, and it was determined by lot that he should rule over the sea. (Hom. Il. 14.156, 15.187, &c.; Hes. Theog, 456.) Like his brothers and sisters, he was, after his birth, swallowed by his father Cronos, but thrown up again. (Apollod. 1.1.5, 2.1.) According to others, he was concealed by Rhea, after his birth, among a flock of lambs, and his mother pretended to have given birth to a young horse, which she gave to Cronos to devour. A well in the neighbourhood of Mantineia, where this is said to have happened, was believed, from this circumstance, to have derived the name of the "Lamb's Well," or Arne. (Paus. 8.8.2.) According to Tzetzes (ad Lycoph. 644) the nurse of Poseidon bore the name of Arne; when Cronos searched after his son, Arne is said to have declared that she knew not where he was, and from her the town of Arne was believed to have received its name. According to others, again, he was brought up by the Telchines at the request of Rhea. (Diod. 5.55.) In the earliest poems, Poseidon is described as indeed equal to Zeus in dignity, but weaker. (Hom. Il. 8.210, 15.165, 186, 209; comp. 13.355, Od. 13.148.) Hence we find him angry when Zeus, by haughty words, attempts to intimidate him; nay, he even threatens his mightier brother, and once he conspired with Hera and Athena to put him into chains (Hom. Il. 15.176, &c., 212, &c.; comp. 1.400.); but, on the other hand, we also find him yielding and submissive to Zeus (8.440). The palace of Poseidon was in the depth of the sea near Aegae in Euboea (13.21; Od. 5.381), where he kept his horses with brazen hoofs and golden manes. With these horses he rides in a chariot over the waves of the sea, which become smooth as he appreaches, and the monsters of the deep recognise him and play around his chariot. (Il. 13.27, comp. Verg. A. 5.817, &c., 1.147; Apollon. 3.1240, &c.) Generally he himself put his horses to his chariot, but sometimes he was assisted by Amphitrite. (Apollon. 1.1158, 4.1325; Eur. Andr. 1011; Verg. A. 5.817.) But although he generally dwelt in the sea, still he also appears in Olympus in the assembly of the gods. (Hom. Il. 8.440, 13.44, 352, 15.161, 190, 20.13.) Poseidon in conjunction with Apollo is said to have built the walls of Troy for Laomedon (7.452; Eurip. Androm. 1014),whence Troy is called Neptunia Pergama (Neptunus and Poseidon being identified, Ov. Fast. 1.525, Heroid. 3.151; comp. Verg. A. 6.810.) Accordingly, although he was otherwise well disposed towards the Greeks, yet he was jealous of the wall which the Greeks built around their own ships, and he lamented the inglorious manner in which the walls
Being the ruler of the sea (the Mediterranean), he is described as gathering clouds and calling forth storms, but at the same he has it in his power to grant a successful voyage and save those who are in danger, and all other marine divinities are subject to him. As the sea surrounds and holds the earth, he himself is described as the god who holds the earth (γαιήοχος), and who has it in his power to shake the earth (ενοσίχθων, κινητὴρ γᾶς). He was further regarded as the creator of the horse, and was accordingly believed to have taught men the art of managing horses by the bridle, and to have been the originator and protector of horse races. (Hom. Il. 23.307, 584; Pind. P. 6.50 ; Soph. Oed. Col. 712, &c.) Hence he was also represented on horseback, or riding in a chariot drawn by two or four horses, and is designated by the epithets ἵππιος, ἵππειος, or ἵππιος ἄναξ. (Paus. 1.30.4, 8.25.5, 6.20.8, 8.37.7 ; Eur. Phoen. 1707; comp. Liv. 1.9, where he is called equester.) In consequence of his connection with the horse, he was regarded as the friend of charioteers (Pind. O. 1.63, &c.; Tzetz. ad Lyc. 156), and he even metamorphosed himself into a horse, for the purpose of deceiving Demeter. The common tradition about Poseidon creating the horse is as follows : -- when Poseidon and Athena disputed as to which of them should give the name to the capital of Attica, the gods decided, that it should receive its name from him who should bestow upon man the most useful gift. Poseidon their created the horse, and Athena called forth the olive tree, for which the honour was conferred upon her. (Serv. ad Virg. Georg. 1.12.) According to others, however, Poseidon did not create the horse in Attica, but in Thessaly, where he also gave the famous horses to Peleus. (Lucan, PPhars. 6.396, &c.; Hom. Il. 23.277; Apollod. 3.13.5.)
The symbol of Poseidon's power was the trident, or a spear with three points, with which he used to shatter rocks, to call forth or subdue storms, to shake the earth, and the like. Herodotus (2.50, 4.188) states, that the name and worship of Poseidon was imported to the Greeks from Libya, but he was probably a divinity of Pelasgian origin, and originally a personification of the fertilising power of water, from which the transition to regarding him as the god of the sea was not difficult. It is a remarkable circumstance that in the legends about this divinity there are many in which he is said to have disputed the possession of certain countries with other gods. Thus, in order to take possession of Attica, he thrust his trident into the ground on the acropolis, where a well of sea-water was thereby called forth; but Athena created the olive tree, and the two divinities disputed, until the gods assigned Attica to Athena. Poseidon, indignant at this, caused the country to be inundated. (Hdt. 8.55; Apollod. 3.14.1 ; Paus. 1.24.3, &c.; Hyg. Fab. 164.) With Athena he also disputed the possession of Troezene, and at the command of Zeus he shared the place with her. (Paus. 2.30.6 ) With Helios he disputed the sovereignty of Corinth, which along with the isthmus was adjudged to him, while Helios received the acropolis. (2.1.6.) With Hera he disputed the possession of Argolis, which was adjudged to the former by Inachus, Cephissus, and Asterion, in consequence of which Poseidon caused the rivers of these river-gods to be dried up. (2.15.5, 22.5; Apollod. 2.1.4.) With Zeus, lastly, he disputed the possession of Aegina, and with Dionysus that of Naxos. (Plut. Sympos. 9.6.) At one time Delphi belonged to him in common with Ge, but Apollo gave him Calauria as a compensation for it. (Paus. 2.33.2, 10.5.3; Apollon. 3.1243, with the Schol.) The following legends also deserve to be mentioned. In conjunction with Zeus he fought against Cronos and the Titans (Apollod. 1.2.1), and in the contest with the Giants he pursued Polybotes across the sea as far as Cos, and there killed him by throwing the island upon him. (Apollod. 1.6.2; Paus. 1.2.4.) He further crushed the Centaurs when they were pursued by Heracles, under a mountain in Leucosia, the island of the Seirens. (Apollod. 2.5.4.) He sued together with Zeus for the hand of Thetis, but he withdrew when Themis prophesied that the son of Thetis would be greater than his father. (Apollod. 3.13.5; Tzetz. ad Lyc. 178.) When Ares had been caught in the wonderful net by Hephaestus, the latter set him free at the request of Poseidon (Hom. Od. 8.344, &c.), but Poseidon afterwards brought a charge against Ares before the Areiopagus, for having killed his son Halirrhothius. (Apollod. 3.14.2.) At the request of Minos, king of Crete, Poseidon caused a bull to rise from the sea, which the king promised to sacri fice; but when Minos treacherously concealed the animal among a herd of oxen, the god punished Minos by causing his daughter Pasiphae to fall in love with the bull. (Apollod. 3.3, &c.) Periclymenus, who was either a son or a grandson of Poseidon, received from him the power of as-suming various forms. (1.9.9, 3.6.8.)
Poseidon was married to Amphitrite, by whom he had three children, Triton, Rhode, and Benthesicyme (Hes. Th. 930; Apollod. 1.4.5,