Poseidon

Olympian God of the Sea

Poseidon at a Glance
Roman name	Neptune
Gender	Male
Type	Deity
Rules over - Patron of	Sea, Earthquakes, Storms, Horses
Symbols	Trident, Fish, Dolphin, Horse, Bull
Sacred Animals	Bull
Parents	Cronus and Rhea
Spouse	Amphitrite
Notable Siblings	Zeus, Hades, Demeter, Hestia, Hera
Important Children	Theseus, Triton, Polyphemus, Belus, Agenor, Neleus, Atlas

Poseidon fathered a lot of children, maybe coming second only to Zeus in that aspect.
Two notable differences between the two are that Poseidon almost always had to force the union, and that the offspring was very often a maleficent being (be it man or monster).

Poseidon also had little luck with becoming the patron of cities. He lost Athens to Athena, Aegina to Zeus, Delphi to Apollo, Argos to Hera and Naxos to Dionysus. When Poseidon fought with Athena over Troezen, Zeus decided that the land should belong to both gods.

In the fight with Athena over the patronage of Athens, each god offered a gift to the city: Poseidon struck a rock at the Acropolis with his trident, creating a spring, while Athena planted an olive tree. Cecrops, the city’s first king, chose Athena, which led to Poseidon flooding west Attica in revenge for his defeat.
Poseidon is considered a very old god, and was possibly once chthonic (=of the underworld), as is suggested by the possible origin of his name, his control over earthquakes, the fact that he fathered a lot of monsters connected with the earth, epithets given to him, as well as by the fact that, even as the god of the seas, he’s still related to springs, lakes and rivers.

Poseidon’s connection with horses

Poseidon was closely connected with horses. According to one myth, when he was newly born, Rhea hid him in a manger and gave Cronus a foal to eat instead of Poseidon in order to save him – though, another myth has it that the first horse sprang from a rock after Poseidon struck the rock with his trident. According to another myth, Poseidon tried to lie with Demeter, who turned into a mare to avoid him. Poseidon then transformed into a stallion and from their union a wild horse, Arion, was born. Poseidon was also the father of the flying horse Pegasus, whom he had with Medusa.

Poseidon’s connection with dolphins

When Poseidon approached Amphitrite to ask her to marry him, she became scared and, wanting to protect her virginity, hid in Atlas’s kingdom. Poseidon then sent out a group to find her, including the dolphin, which located her in the isles of Atlas, reassured her of Poseidon’s good intentions and convinced her to meet him. According to the myth, Poseidon made it sacred and named the constellation Delphinus in its honour.

Poseidon’s connection with bulls

In Crete, when Minos was trying to establish himself as king of the island, he asked Poseidon to display a sign in front of everyone that would indicate he had the gods’ favour to be king. Poseidon went on to produce a beautiful bull from the waves for everyone to see, and Minos was crowned king of Crete. He did, however, make the mistake of not sacrificing the bull to Poseidon, as he thought it would be a pity to kill such a beautiful animal. This enraged Poseidon, who made Pasiphae, Minos’s wife, fall in love with the bull and from their union the Minotaur was born, who was half man, half bull, and fed only on human flesh.

Etymology

The name “Poseidon” possibly originates from the Greek πόσις (=man, husband) and δα(earth).