Indo-Aryan migration hypothesis

Indo-Aryan migration models discuss scenarios around the theory of an outside origin of Indo-Aryan peoples, an ascribed ethno-linguistic group that speaks Indo-Aryan languages, the predominant languages of North India. Proponents of Indo-Aryan origin outside of India generally consider migrations into South Asia and Anatolia (ancient Mittani) from Central Asia to have started around 1500 BCE, as a slow diffusion during the Late Harappan period, which led to a language shift in northern India. The Iranian languages were brought into Iran by the Iranians, who were closely related to the Indo-Aryans.

The Proto-Indo-Iranians, from which the Indo-Aryans and the Iranians developed, formed as a distinguishable culture at the Central Asian steppes north of the Caspian Sea as the Sintashta culture (2100–1800 BCE), present-day Kazakhstan, and developed further as the Andronovo culture (1800–1400 BCE), around the Aral sea. The proto-Indo-Iranians then migrated southwards to the Bactria-Margiana Culture, from which they borrowed their distinctive religious beliefs and practices. The Indo-Aryans split off around 1800-1600 BCE from the Iranians, whereafter the Indo-Aryans migrated into Anatolia and the northern part of the Indian subcontinent (modern India, Pakistan and Nepal), while the Iranians moved into Iran, both bringing with them the Indo-Aryan languages.

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