Poseidon was a god in Greek mythology. In art, he was often portrayed holding a trident -- a pitchfork-shaped fishing spear -- and commanding a chariot pulled by horses or a hippocampus. He was said to have a palace made of coral and gems on the ocean floor.

The Minoans of Ancient Akrotiri in Greece considered Poseidon to be the ruler of the Aegean sea. His gifts to them included the creation of new islands, calming the seas, and saving ships and sailors. When he was angered, it was believed that Poseidon struck the ground with his trident causing earthquakes, floods, and shipwrecks. When a volcano erupted, burying the city of Akrotiri under ash and lava, the catastrophe was explained as the wrath of Poseidon, the "earth shaker".

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