Iyers are an ethnoreligious community of Tamil-speaking Hindu Brahmins. Most Iyers are followers of the Advaita philosophy propounded by Adi Shankara and adhere to the Smarta tradition. This is in contrast to the Iyengar community, who are adherents of Sri Vaishnavism. The Iyers and the Iyengars are together referred to as Tamil Brahmins. The majority of Iyers reside in Tamil Nadu, India.

The Smarta tradition, also called Smartism, is a movement in Hinduism that developed and expanded with the Puranas genre of literature. It reflects a synthesis of four philosophical strands, namely Uttara Mīmāṃsā, Advaita, Yoga, and theism. The Smarta tradition rejects theistic sectarianism, and is notable for the domestic worship of five shrines with five deities, all treated as equal – Ganesha, Shiva, Shakti, Vishnu and Surya. The Smarta tradition contrasted with the older Shrauta tradition, which was based on elaborate rituals and rites. There has been a considerable overlap in the ideas and practices of the Smarta tradition with other significant historic movements within Hinduism, namely Shaivism, Brahmanism, Vaishnavism, and Shaktism.