Why is Poseidon so important in Greek mythology?

poseidon was one of the three original greek gods along with hades and Zeus. the three of them were believed to stop the evil titians rule and control the earth Zeus claimed the heavens and created the people while hades got the underworld where the dead went and poseidon was given the seas to control. poseidon is also known as god of the storms, earthquakes and horses. he is represented by the symbols trident, fish dolphin, horse and bull. his parents wre Cronus and Rhea. his children theseus, Triton and polyphemus.