Janapadas :

The small states that came into existence in north India in the post-vedic period were known as Janapadas.

• The post-Vedic period is defined as the period from 1000 BC to 600 BC.
• Many small states were scattered across the country, from Afghanistan in the northwest to Bihar, Bengal, and Odisha in the east, and Maharashtra in the south.
• The Janapadas were either monarchies or republics.
• Some Janapadas held ganaparishads in Santhagar.
• Each Janapada had its own currency.

Mahajanapadas :

• Some janapadas grew stronger over time and expanded their geographical boundaries. These janapadas became known as mahajanapadas.
• Up until the sixth century BCE, sixteen mahajanapadas held special significance.
• Among them, Kosala, Vatsa, Avanti, and Magadha grew in power.

Kosala :

• Kosala was situated in the Himalayan foothills.
• Shravasti was its capital. Prasenjit of Kosala was a contemporary of Gautam Buddha and Vardhaman Mahavir.
• He was a capable commander.
• Later, the state of Kosala merged with the state of Magadha.

Vatsa :

• Kaushambi, later known as Kosam, was Vatsa's capital.
• Buddhist literature and Bhasa's Sanskrit plays teach us about the valiant Vatsa king Udayana.
• Vatsa was well-known for its high-quality cotton textiles.
• Following the death of King Udayana, the State of Vatsa was unable to maintain its independence for long.
• Avanti mahajanapada's king conquered the state.

Avanti :

• Ujjayani was Avanti's capital and a well-known trade centre.
• Pradyot was one of Avanti's most powerful kings.
• The Avanti State was absorbed into the Magadha Empire during the reign of King Nandivardhan.

Magadha :

• Magadha was spread across the Ganga and Shon basins.
• Magadha's capital was Rajgriha.
• King Bimbisara’s palace was built by the architect Mahagovind.
• Jeevaka, the famous physician, was at Bimbisara's court.

Nanda dynasty :

• Nanda dynasty ruled over Magadha empire from 364 BC to 324 BC.
• The Nanda rulers set-up an efficient administrative machinery to rule over the vast empire,
• They standardized Weights and measures.
• They had ‘four-fold army’ which included infantry, cavalry, chariots and elephants.
• Magadha, under the Nanda rulers was the first empire in ancient India.