In the prehistory of the Indian subcontinent, the Iron Age succeeded Bronze Age India and partly corresponds with the megalithic cultures of India. Other Iron Age archaeological cultures of India were the Painted Grey Ware culture (1300–300 BCE) and the Northern Black Polished Ware (700–200 BCE). This corresponds to the transition of the Janapadas or principalities of the Vedic period to the sixteen Mahajanapadas or region-states of the early historic period, culminating in the emergence of the Maurya Empire towards the end of the period. The earliest evidence of iron smelting predates the emergence of the Iron Age proper by several centuries.