Indo-Aryan migration is a necessary corollary of any model of Indo-European origins that locates the original Indo-European homeland outside the Indian subcontinent.The Indo-Aryans derive from an earlier Proto-Indo-Iranian stage, usually identified with the Bronze AgeAndronovo culture at the Caspian Sea, and Indo-Aryan migration to India is consequently assumed to have taken place in the Middle to Late Bronze Age, contemporary to the Late Harappan phase in India.
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