The Asuras are the evil gods of Hindu (Vedic) religion, contrasted to their benevolent counterparts the Devas. However, further west in Persian (Zoroastrian) religion, the Azuras (Ahuras) are the benevolent deities. Their opponents being the "evil" Daevas. Pointing to a common Indo-European ancestry for both religions, and a conflict that might derive from prehistoric religious disputes.
Etymologically the term "Asura" seems to be related to another Indo-European group of deities, the "Aesir". Both names are thought to derive from ancient terms for "life force" and "godhood".