Janapadas were realms, republics, and kingdoms that prospered during the Vedic Period into the late Bronze and Iron Ages. These Janapadas produced some the first coins in the history of India and the world. They existed between the years, 1200 BCE and 6th century BCE and comprised of a total of 56 states spread across the Indian Subcontinent. These Janapadas transformed into 16 Mahajanapadas when the states or kingdoms were annexed by their more powerful neighbours. Some of the states remained independent.
Read more about Janapada history at Mintage World.