Haryana, eastern Rajasthan, and northern Madhya Pradesh.

While significant attempts have been made recently to identify the exact locations of the individual Upanishads, the results are tentative. Witzel identifies the center of activity in the Brihadaranyaka Upanishad as the area of Videha, whose king, Janaka, features prominently in the Upanishad. The Chandogya Upanishad was probably composed in a more western than eastern location