The 6th–5th centuries BCE are often regarded as a major turning point in early Indian history. During this period, India’s first large cities since the demise of the Indus Valley civilization arose. It was also the time of the rise of sramana movements (including Buddhism and Jainism), which challenged the religious orthodoxy of the Vedic period.

The Buddhist Anguttara Nikaya, at several places,^[15] gives a list of sixteen great states:

1. Anga
2. Assaka (or Asmaka)
3. Avanti
4. Chedi
5. Gandhara
6. Kasi
7. Kamboja
8. Kosala
9. Kuru
10. Magadha
11. Malla
12. Matsya (or Maccha)
13. Panchala
14. Surasena
15. Vajji
16. Vatsa (or Vamsa)

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