Matsya :-
The country of the Matsya or Machcha tribe lay to the south of the Kurus and west of the Yamuna, which separated them from the Panchalas. It roughly corresponded to the former state of Jaipur in Rajasthan, and included the whole of Alwar with portions of Bharatpur. The capital of Matsya was at Viratanagara (modern Bairat) which is said to have been named after its founder king Virata. In Pali literature, the Matsyas are usually associated with the Surasenas. The western Matsya was the hill tract on the north bank of the Chambal. A branch of Matsya is also found in later days in the Vizagapatam region. The Matsyas had not much political importance of their own during the time of Buddha. King Sujata ruled over both the Chedis and Matsyas, thus showing that Matsya once formed a part of the Chedi kingdom.
Panchala :-
The Panchalas occupied the country to the east of the Kurus between the mountains and river Ganges. It roughly corresponded to modern Budaun, Farrukhabad and the adjoining districts of Uttar Pradesh. The country was divided into Uttara-Panchala and Dakshina-Panchala. The northern Panchala had its capital at Adhichhatra or Chhatravati, while southern Panchala had its capital at Kampilya or Kampil in the Farrukhabad District. The famous city of Kanyakubja or Kanauj was situated in the kingdom of Panchala. Originally a monarchical clan, the Panchals appear to have switched to republican corporation in the 6th and 5th centuries BCE. In the 4th century BCE, Kautiliya's Arthashastra.
Surasena :-
The country of the Surasenas lay to the east of Matsya and west of Yamuna. This corresponds roughly to the Brij region of Uttar Pradesh, Haryana and Rajasthan. and Gwalior region of Madhya Pradesh. It had its capital at Madhura or Mathura. Avantiputra, the king of Surasena, was the first among the chief disciples of Buddha, through whose help Buddhism gained ground in Mathura country.
Vajji :-
Vajji or Vrijji was a confederacy of neighbouring clans including the Licchavis and one of the principal mahājanapadas of Ancient India. The area they ruled constitutes the region of Mithila in northern Bihar and their capital was the city of Vaishali.
Vatsa :-
The Vatsas or Vamsas are called to be a branch of the Kurus. The Vatsa or Vamsa country corresponded with the territory of modern Allahabad in Uttar Pradesh. It had a monarchical form of government with its capital at Kausambi (identified with the village Kosam, 38 miles from Allahabad). Kausambi was a very prosperous city where a large number of wealthy merchants resided. It was the most important entreport of goods and passengers from the north-west and south. Udayana was the ruler of Vatsa in the 6th-5th century BCE.
