This is a list of ancient Indo-Aryan peoples and tribes that are mentioned in the literature of Indic religions. From the second or first millennium BCE, ancient Indo-Aryan peoples and tribes turned into most of the population in the northern part of the Indian subcontinent – Indus Valley (roughly today's Pakistan), Western India, Northern India, Central India, and also in areas of the southern part like Sri Lanka and the Maldives through and after a complex process of migration, assimilation of other peoples and language shift.