The name “Proteus” is an ancient word meaning “first”, “firstborn”, and “primordial”.
The sailors often called Proteus the “Old Man of the Sea” and considered him their protector in their voyages. As Homer tells us, he was submissive to Poseidon and knew all the depth of the sea and their secrets. He was also gifted with clairvoyant abilities and he could transform into anything he wanted whether that would be an animal, a plant, a bird, and even fire or water.
In the Odyssey, Homer mentions that Proteus lived in the small island of Pharos at the Mediterranean coast of Egypt, at the mouth of the Nile. When Menelaus was returning from Troy with him Helen, the strong winds of the Aegean Sea brought them to Egypt. There Menelaus, by chance, came across the wise and willing daughter of Proteus, Eidothea, who gave him instructions on how he could extract useful information from her father for the return voyage. Eidothea even revealed to him that her father could tell him what had happened in his household, pleasant or unpleasant, while he was away.
Menelaus then applied the following trick, following her advice: he and three more of his companions dressed themselves with freshly skinned sealskins and lay among the seals of Proteus at noon.
When Proteus came out of the sea, he counted his seals, but did not suspect the trap and hurdled among them. Once he fell asleep, Menelaus grabbed him along with his companions and held him tight. Proteus was trying to get away from them and transformed into a lion, a dragon, a tiger, a boar, and then into a tree and even water. But they did not get discouraged and did not stop fighting with him until he started assuming back his original form before he fell asleep.
Then Proteus exhausted, replied to Menelaus questions and that was how he found out that in order for the Gods to reveal to him the way of return he had to sail up the Nile and present them with an offering of one hundred oxen. Also, he was told that it was not written for him to die, because Zeus saw him as a son in law, because of Helen, and that he would treat him favorably. He would lead him after death to the Elysian Fields.