The Nanda dynasty ruled in the northern part of the Indian subcontinent during the 4th century BCE, and possibly during the 5th century BCE. The Nandas overthrew the Shaishunaga dynasty in the Magadha region of eastern India, and expanded their empire to include a larger part of northern India. Ancient sources differ considerably regarding the names of the Nanda kings, and the duration of their rule, but based on the Buddhist tradition recorded in the Mahavamsa, they appear to have ruled during c. 345–322 BCE, although some theories date the start of their rule to 5th century BCE.

The Nandas built on the successes of their Haryanka and Shaishunaga predecessors, and instituted a more centralised administration. Ancient sources credit them with amassing great wealth, which was probably a result of introduction of new currency and taxation system. Ancient texts also suggest that the Nandas were unpopular among their subjects because of their low status birth, excessive taxation, and their general misconduct. The last Nanda king was overthrown by Chandragupta Maurya, the founder of the Maurya Empire, and the latter's mentor Chanakya.

Modern historians generally identify the ruler of the Gangaridai and the Prasii mentioned in ancient Greco-Roman accounts as a Nanda king. While describing Alexander the Great's invasion of north-western India (327–325 BCE), the Greco-Roman writers depict this kingdom as a great military power. The prospect of a war against this kingdom, coupled with the exhaustion resulting from almost a decade of campaigning, led to a mutiny among Alexander's homesick soldiers, putting an end to his Indian campaign.