Vatsa-deśa was an ancient kingdom of central Bhāratavarsha. It lay in the region around Kauśāmbī, which is the area of the modern Allahabad-Banda district. The Mahābhārata names it in the Ambopākhyāna Parva of the Udyoga Parva, in connection with the river Ambā.

The kingdom

Vatsa-deśa was one of the significant kingdoms of the Dvāpara period. It was known for its culture and its political importance in the region of the Yamunā valley.

The Ambā nadī

In the Ambopākhyāna, Vatsa-deśa is the land through which the Ambā nadī flows. This river is linked to the long tapas (austerity) of Ambā. During her twelve years of wandering, Ambā took the form of a river in part, and that river is the Ambā nadī.

Gaṅgā had warned Ambā that her consuming hatred would turn her into a crooked river. This came true in Vatsa-deśa. Ambā’s energy became a river of crooked course here. After that she took up her final course of tapas and gave up her body in the fire.

Sources

Mahābhārata, Udyoga Parva, Ambopākhyāna Parva