How many ancient kingdoms were there in India?

16.

As mentioned by Chintaman Vinayak Vaidya in his book “Epic India, or, India as described in the Mahabharata and the Ramayana”, ancient texts contemporary with Buddha list 16 ancient kingdoms in India. It is understood that such list is not exhaustive ‘“ only the main kingdoms are mentioned; the total number of ancient kingdoms may be over 100.