Wikipedia
The Hindu religious text Manusmriti describes Brahmavarta as the region between the rivers Saraswati and Drishadwati in India. The text defines the area as the place where the "good" people are born, with "goodness" being dependent on location rather than behaviour. The name has been translated in various ways, including "holy land", "sacred land", "abode of gods" and "the scene of creation".
The precise location and size of the region has been the subject of academic uncertainty. Some scholars, such as the archaeologists Bridget and Raymond Allchin, believe the term Brahmavarta to be synonymous with the Aryavarta region.
According to Manusmriti, the purity of a place and its inhabitants decreased the further it was from Brahmavarta. Aryan (noble) people were believed to inhabit the "good" area and the proportion of Mleccha (barbarian) people in the population rose as the distance from it increased. This implies a series of concentric circles of decreasing purity as one moved away from the Brahmavarta centre.
The translation of Manusmriti made by Patrick Olivelle, a professor of Sanskrit, says:
The French Indologist and convert to Hinduism, Alain Daniélou, notes that the Rig Veda, which is an earlier Hindu text, describes the region later known as Brahmavarta as the heartland of Aryan communities and the geography described in it suggests that those communities had not moved much beyond the area. He says that later texts, contained in the Brahmanas, indicate that the centre of religious activity had moved from Brahmavarta to an adjacent area south-east of it known as Brahmarisihidesa. Again, some sources consider Brahmarisihidesa to be synonymous with Brahmavarta.