The Nishadha(IAST: Niṣadha) was a tribe of ancient India that lived in a country of the same name[1][2]
Veerasena was a king of the Nishadha kingdom, and the father of Nala. Nala, the son of Veerasena, became the king after his father. He was the husband of Damayanti, and their story is told in the Mahabharata.[3][4]: 136 Their story is also told in Shriharsha's sanskrit epic named Naishadha Charita.
The Niṣādas are surely quite distinct from the Niṣādhas, with whom they are often confounded but who in all probability belonged to the Aryan fold.
The Niṣādhas, residing in the Niṣādha country were obviously Aryan tribes and they should not be confused with the Niṣāda, the non-Aryan tribe.