The book/movie? Vastly so.
In Greek mythology Poseidon was the main sea god and other sea gods merged into his aspects.
After Poseidon was born, his father, Cronus, attempted to eat him, but he was saved by his brother, Zeus. In other versions, his mother saved him and he was raised by Telchines.
Yes. Poseidon greatly favoured the Greeks in the Trojan war, and in some versions he is said to have given Odysseus the idea for the Trojan horse.
Poseidon's favorite mortal is often considered to be Theseus, the legendary hero of Athens. According to mythology, Poseidon aided Theseus in various endeavors, including his journey to Crete to confront the Minotaur. Additionally, some versions of the myth suggest that Poseidon fathered Theseus, further solidifying their bond. However, other mortals like Acis and Polyphemus also have strong connections with the sea god, showcasing Poseidon's varied relationships with humans.
There are different versions of the story.In Homer's Odyssey:Odysseus and his crew had blinded Poseidon's son, the Cyclops Polyphemus and then taunted Polyphemus afterwards. Polyphemus prayed to his father for revenge on Odysseus.In other versions, including the Odyssey movie: Odysseus had believed he defeated Troy without the help of the gods. So Poseidon wanted Odysseus to learn that man is nothing without the gods. Especially because it was he who had sent the sea serpent to kill the soothsayer who told the Trojans to burn the wooden horse.Poseidon was angry at Odysseus because Odysseus blinded Poseidon's son, Polyphemus, who was a cyclops.
Triton just follows Poseidon, his father, about the sea. (Poseidon has other sons too, but they are not in the sea).
Poseidon's brothers were Zeus and Hades
Neptune, was the Roman equivalent of the Greek Poseidon. I've never heard of any other names for him.
yes, poseidon was married to Amphitrite, which was nereu's daughter.
Neptune
Poseidon fought with other gods: Zeus himself, Hera, Dionysus, Helius
Poseidon. On the other hand the Romans new the god of the sea as Neptune.
Poseidon helped the Greeks win the Trojan War