The Snake symbol has different meanings in many Native American tribes. In the Pueblo tribe snakes are symbolic of fertility, in the Ojibwa culture the snake symbolizes healing and due to its ability to shed its skin other traditions associate the snake with re-birth. All of these symbolize the snake as a benign creature but many ancient cultures believe that the snake represents the Underworld and is strongly associated with serpent, which is basically a large snake, although usually depicted as a monster.
In Lakota Sioux and Blackfoot mythology, Unhcegila is a snake or serpent-like monster that was responsible for many unexplained disappearances and deaths. She could swallow a human in one piece or squash him with her weight. Uncegila was a massive reptile that crawl very fast underground and moved even faster on the land. The touch of Unhcegila slime made flesh rot away and caused the ground she passed to become infertile.
Snake Myth and Legend: The Avanyu symbol is one of the many snake-like deities that figure in the mythology of some Native American tribes, notably the Pueblo. The Avanyu symbol represented the storm bringer and was connected with lightning, thunderstorms and the guardian of water.
There is a legend that in the beginning of the world winged snakes or serpents reigned upon the earth and snake symbols depict this event. There is a symbolic relationship between the sun and the snake because life remains in the snake, until sunset even though the snake might be cut into a dozen parts. The Hopi Indians consider the snake to be in close communication with the Earth Spirit. Therefore, at the time of their annual snake dance they send their prayers to the Earth Spirit by first specially sanctifying large numbers of snakes and then liberating them to return to the earth with the prayers of the tribe.