The alwar or azhwars (Tamil: ஆழ்வார்கள், āzvārhaḷ [aːɻʋaːr], ‘those immersed in god’) were Tamil poet saints of south India who lived between the sixth and ninth centuries A.D. and espoused ‘emotional devotion’ or bhakti to Visnu-Krishna in their songs of longing, ecstasy and service. Sri Vaishnava orthodoxy posits the number of alvars as ten, though there are other references that include Andal and madhurakavi, making the number twelve. The devotional outpourings of Alvars, composed during the early medieval period of Tamil history, helped revive the bhakti movement, through their hymns of worship to Vishnu and his Avatars. They praised 108 of this deity's holy abodes in their hymns, known as the Divya Desams. Together with the contemporary sixty three Saiva Nayanars, they are accounted as South India's 75 Apostles of Bhakti because of their importance in the rise of the Hindu Bhakti movement. The collection of their hymns is known as Divya Prabandha.

The Bhakti literature that sprang from Alvars has contributed to the establishment and sustenance of a culture that broke away from the ritual-oriented Vedic religion and rooted itself in devotion as the only path for salvation. In addition they helped to make the Tamil religious life independent of a knowledge of Sanskrit. As part of the legacy of the Alvars, five Vaishnava philosophical traditions (sampradayas) have developed at the later stages.