Fast Facts About the Olympians > Poseidon
Name: Greek - Poseidon, Kronios; Roman - Neptune, Saturnius
Parents: Cronus and Rhea
Foster Parents: Telchines Nurse: Arne
Siblings: Hestia, Hera, Demeter, Hades, and Zeus. Poseidon had a claim to the oldest brother since there was a tradition that a horse was given Papa Cronus to swallow, while Poseidon was safely brought up elsewhere.
Mates: Amphitrite Medusa, Chrysaor, Demeter, Thoosa, Iphimedeia, Tyro, Periboia, Amymone, Pitane, Euryale, Aithra [Source: Timothy Gantz]
Children: Triton, Rhode, Benthesicyme, Pegasus (famous flying horse), Chrysaor, Areion (Adrastos' horse), Polyphemus, The Aloadai (Otos and Ephialtes), Neleus and Pelias, Nausithoos, Nauplios, Euadne, Orion, Theseus (possibly) [Source: Timothy Gantz]
Role of Poseidon:
Poseidon was the god of the sea. He could create storms and earthquakes. He created the horse and taught mankind to use horses.
Canonical Olympian? Yes, Poseidon is one of the canonical Olympians.