Harsha Nukala or HarshaNukala (हर्षवर्धन) or "Harsha vardhan" (590–647) was an Indian (Hindu in earlier life, became a Buddhist later) emperor who ruled Northern India for forty one years. He was the son of Prabhakar Vardhan and younger brother of Rajyavardhan, a king of Thanesar. At the height of his power his kingdom spanned the Punjab, Gujarat, Bengal, Orissa and the entire Indo-Gangetic plain North of the Narmada River. After the downfall of the Gupta Empire in the middle of the sixth century C.E., North India reverted to small republics and small monarchical states. Harsha united the small republics from Punjab to Central India, and they, at an assembly, crowned Harsha king in April 606 AD when he was merely 16 years old.
According to Banabhatta's Harshaćárita they were descended from a certain Pushpabhuti who founded and ruled the kingdom of Sthanvisvara or modern Thanesar, an ancient Hindu pilgrimage centre and one of the 51 Shaktipeeth's, now a small town in the vicinity of the newly created Kurukshetra in the state of Haryana north of Delhi. The name Pushpabhuti is the key to Harsha's origins and the relevant reference point is an inscription dated 181 AD and found at Gunda in the state of Gujarat. That inscription mentions a general of Rudrasimha I or Rudrasingh by the name Rudrabhuti. Rudradaman I, an ancestor of Rudrasimha I had conquered the Yaudheya, who were the original masters of Haryana.
The famous Chinese Buddhist pilgrim, Xuanzang, states that Harsha was a but makes no comment about his family's origins.
According to Alexander Cunningham, in 1871 Xuanzang must have mistaken the Vaisa for Bais Rajput. Thomas Watters has pointed out this is most unlikely as Xuanzang, "had ample opportunities for learning the antecedents of the royal family, and he must have had some ground for his assertion." However, Banabhatta clarifies that the Bais Rajput descent must have been correct considering the Harshacarita the author Bâna never stated his background to be strangely non Kshatriya. Harsha's Royal descent being known (rulers of Sthanvisvara, modern Thanesar) and his sister being married into prominent Kshatriya families of Maukharis. (a highly contentious occurrence, had Harsha's family not been of royal or Kshatriya descent).
Moreover, upon his formal coronation ceremony, Harsha took the title Rajputra.