According to Vedic myth, Ananta is a name given to Sesha, the chief of the Nagas and ruler of Patala. He is one of a group of seven mahanagas, nagaraja, or nagadevas (snake deities). He has one thousand heads.
Shortly before the death of Bala-Rama (called Silappadikaram by the ancient Tamils), Sesha emerged from his mouth, making him an incarnation of Bala-Rama. It is said he held back the waters until overcome by Indra. For this reason he is also equated with Vritra, a dragon (or demon) slain by Indra for causing a drought to hinder the invading Hindus. In India, Vritra is a spider god also known as Ahi, the son of Danu, the serpent god. Vasuki is another Naga ruler who seems to have been a kinsman of Sesha.