For early history see Dagar Dynasty
The Danga/Dagar family were the hereditary Deshmukh Chaudhary of Merta Pargana(District). The Dangas were originally residence of the countryside of Nagaur. Differences among them surfaced and, consequently, the Dangas first migrated to the village of Kathoti of Jayal and then to Harsor. Finding It difficult to reside there, they continued their search for new settlements.
At Merta, Rao Var Singh was desperately in the quest of colonisers to cultivate the barren land of his ‘fiefdom’. This news reached the caste-leader of the Dangas named Thir Raj who subsequently met the Rao. He offered his services and said that if he was invited, he would colonize all the villages. The Rathor chief agreed to all the demands of the colonizer, and Thir Raj was accorded the status of the head of the pargana (desmukh chaudhary) of the entire territory. His headquarter was established at Dangawas an old locality within Merta itself.
The influence of Thir Raj over the area was overwhelming. He held a position of eminence amongst his caste fellows. By exercising his influence, he brought the Jats of Swalakh (an old name of Nagaur) and got settled in Merta assuring them about their welfare. Consequently, a process of settlement was heralded and village were colonized continuously. In this way the entire area of Merta was settled and populated, making the land productive. The words of Nainsi are: pachhe Merta ra sara gaon basiya, dharati awandan hui. The descendant of Thir Raj remained the Deshmukh Chaudharies of Merta when Merta came under the rule of the Mughals.