The debate mostly exists among the scholars of Hindu religion and the history and archaeology of India, whereas historical linguists nearly unanimously accept the migration model of Indic origins.
300 BCE, reported to have heard of a traditional list of 153 kings that covered 6042 years, beyond the traditional beginning of the Kaliyuga at 3102 BCE. For Aurobindo, an "Aryan" was not a person who belonged to a particular race, but a person who "accepted a particular type of self-culture, of inward and outward practice, of ideality, of aspiration." Aurobindo denied the historicity of a racial division in India between "Aryan invaders" and a native dark-skinned population.
Along with this comes a redating of historical personages and events, in which the Buddha is dated to 1700 BCE or even 3139/8 BCE, and Chandragupta Maurya (c. Nevertheless, he did accept two kinds of culture in ancient India, namely the Aryan culture of northern and central India and Afghanistan, and the un-Aryan culture of the east, south and west.
The idea of an Aryan "invasion" was fueled after the discovery of the Indus Valley Civilisation, also called Harappan Civilisation.
The Indus Valley Civilisation underwent decline at precisely the period at which the Indo-Aryan migration occurred.
The idea of "Indigenous Aryans" also implies a migration "Out of India" to Europe and east Asia.