This was not the first time the Romans had borrowed the creativity of the Greek.
Even though both the gods were attributed the same authority, looking over the matters relating to the sea, both Poseidon and Neptune differed from each other in respect to their literate. While the Greek god was regarded as the brother Zeus, the god of lightning, and Hades, the god of the underworld, the Roman god of sea is the brother of Pluto and Jupiter. The Greek mythology narrates a much more comprehensive detail about their god of sea than the Roman mythology.
Another thing that makes Poseidon and Neptune a little different from each other is that the former is normally associated with nothing but the sea, whereas the latter is also called the horse god.
Due to the severe dependency of their populations on the sea and oceans, the ancient Romans were convinced that the sea was being controlled by a god. They named the god Neptune and begin to worship him in order to receive his blessings. The ancient Romans believe that if the god of sea was happy with them, he would be kind to them, bring them fish, look after their ships and most importantly, not flood them. Neptune is said to have two siblings, namely Jupiter and Pluto.
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Poseidon is said to be the offspring of Cornus and Rhea and the brother of Zeus, Hades, Hestia, Demeter and Hera. He is also depicted as the husband of the sea goddess Amphitrite and the father of Rode and Triton. When Zeus managed to overthrow Cronus, he and his brothers divided the sky, sea and earth among themselves. Poseidon got to be the king of the sea, or according to the mortals, the god of the sea. He was depicted as the saviour of the people who were travelling by sea, using his supernatural powers to protect them from harm. He was also believed to have a bad temper, flooding populations if they angered him.
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