Magadha was a region and one of the sixteen Mahajanapadas, 'Great Kingdoms' of the Second Urbanization (600–200 BCE) in what is now south Bihar (before expansion) at the eastern Ganges Plain. Magadha was ruled by Brihadratha dynasty, Pradyota dynasty (682–544 BCE), Haryanka dynasty (544–413 BCE), the Shaishunaga dynasty (413–345 BCE) and the Mauryan dynasty by the end of it. Villages had their own assemblies under their local chiefs called Gramakas. Their administrations were divided into executive, judicial, and military functions.

Magadha played an important role in the development of Jainism and Buddhism. It was succeeded by four of northern India's greatest empires, the Nanda Empire (c. 345–322 BCE), Maurya Empire (c. 322–185 BCE), Shunga Empire (c. 185–78 BCE) and Gupta Empire (c. 319–550 CE). The Pala Empire also ruled over Magadha and maintained a royal camp in Pataliputra.

The Pithipatis of Bodh Gaya referred to themselves as Magadhādipati and ruled in parts of Magadha until the 13th century.