Sosipolis, in Grecian mythology, was a patron god of the State, venerated among the Eleans. His worship originated, as it is fabled, at a time when the Arcadians had invaded Elis. A woman appeared among the Eleans, and related that in a dream the child at her breast had been pointed out to her as the savior of the State. The leaders thereupon placed the child naked before their ranks, and when the battle began it was metamorphosed into a serpent, which frightened the Arcadians and won the victory. After the battle the snake disappeared, and on the spot where it was last seen a temple was erected to the child and his mother, Eileithyia (Pausan. 6, 20, 2; 3, 25, 4). See Smith, Dict. of Biog. and Mythol. s.v.; Vollmer, Worterb. d. Mythol. s.v.