Nagabhata has been named as the founder of the imperial Pratihara dynasty in the Gwalior inscription of his descendant Mihira Bhoja.
The Jain text Harivamsa (783–784 CE) states that his grand-nephew Vatsaraja was the king and a "son of Avanti soil" (Avanti-bhūbriti).
[5] Based on this, a number of historians, including R. C. Majumdar and Baij Nath Puri, hold the view that Ujjain, the capital of Avanti, was the original home of Nagabhata's dynasty.
His theory is based on the identification of Nagabhata with Nāhada, who is mentioned in a medieval Jain prabandha (legendary chronicle) as a "soldier of fortune" and the first ruler of his family.
The text states that Nāhada made Jābālipura (identified with Jalor) his capital and came into conflict with a Muslim ruler, whom he defeated.
[5] The 756 CE Hansot inscription of a Chahamana ruler Bhartrvaddha records the grant of a village during the reign of his overlord Nagavaloka.
If this assumption is true, it is possible that after the Rashtrakutas left, Nagabhata regained his power, and conquered the area around Bhrigukachchha (Bharuch), where a Chahamana branch ruled under his suzerainty.
[14] An inscription of Gallaka, a subordinate of Vatsaraja, in the year 795 regards Nagabhata I as the one who had acquired victory over the "invincible Gurjaras" and obtained fame.