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The earliest reference to the Magadha people occurs in the Atharva-Veda where they are found listed along with the Angas, Gandharis, and Mujavats. Magadha played an important role in the development of Jainism and Buddhism, and two of India's greatest empires, the Maurya Empire and Gupta Empire, originated from Magadha. These empires saw advancements in ancient India's science, mathematics, astronomy, religion, and philosophy and were considered the Indian "Golden Age". The Magadha kingdom included republican communities such as the community of Rajakumara. Villages had their own assemblies under their local chiefs called Gramakas. Their administrations were divided into executive, judicial, and military functions.

Where is the earliest mention of Magadha people?
Atharva-Veda