Neptune was the Roman god who ruled over the seas and was identified with the Greek god Poseidon.
In Roman religion, Neptune was associated with freshwater and the sea. Romans later connected him closely with Poseidon, adopting many Greek myths, symbols, and stories for their own deity. Like Poseidon, Neptune was shown with a trident and was also linked with horses and dolphins.
Neptune’s wife was Salacia, a goddess associated with salt water. His principal Roman festival, the Neptunalia, was traditionally held on July 23, during the hottest and driest part of summer. Its timing suggests that Neptune originally had an important connection with springs and freshwater sources, not only the open sea.
A common mix-up is confusing Neptune with the planet of the same name. The planet was named after this sea god, and its astronomical symbol resembles his trident. Mars was the god of war, Pluto ruled the underworld, and Jupiter was the chief sky god.