Definition: Perithous, son of Dia and Ixion or Zeus, was the prince of Lapithae and a friend of Theseus. Perithous married Hippodamia. At his wedding feast, a battle broke out between the Lapithae and the Centaurs. In exchange for Theseus' help rescuing his bride from the centaurs, Perithous helped Theseus in the abduction of Helen (later Helen of Troy), and went with Theseus to the Underworld to carry off Persephone. Chained up in the Underworld as punishment, Perithous had to be rescued by Hercules.