Bhat records hold that the origins of the surname were found in a split between the Tyagis and the Brahmin subcaste. BhumiharBrahmin. Bhumihar are said to be direct descendants of Parashuram, the sixth avatar of Vishnu. Parashuram requested that the Bhumihar renounce all future bhiksha, and instead impart their knowledge and administration for religious functions without donation, in turn dedicating themselves to the development of agriculture in northern India. Those that obeyed Parashuram were given the surname 'Tyagi' to commemorate their sacrifice.
This assertion is not without debate, however. Other sources maintain that the origins of the surname hold a connection with Janmejay, the first Hindu king during the age of kalyug, approximately 3000 BCE. Janmejay was the great-grandson of Arjuna, the protagonist of the Bhagavad Gita. According to alternate bhat records, Janmejay organized a NagYagna, for a bloody war waged against the Nagas. Yagnas were generally performed as a ritual of purification for sins and bloodshed committed during war. At this ceremony, the most learned and renowned of Brahmins versed in performing the art of sacrifice were invited from across the northern subcontinent to administer the ceremony. According to Vedic literature, the Yajinika of such an elaborate ceremony was required to be a master scholar in scripture, mathematics, and astronomy. At the end of the Yagna, a bhiksha was offered to the Brahmins in exchange for their services. Janmejay, per tradition, offered the visiting priests wealth in the form of gold, livestock (particularly cows), houses, horse driven chariots, and clothes, among other things, in gratitude for their services.
Beyond this, however, Janmejay wished that the scholars and priests remained near his capital regions of Indraprashtha, or modern-day Delhi, as well as in Hastinapura, the older capital of the Kuru dynasty. Per records, Janmejay offered the visiting Brahmins a total of 2444 villages in exchange for retaining them near his capital cities.
While Brahmins did not traditionally cultivate land, by tradition the Brahmin priests could not refuse the bhiksha offered at the end of a ceremony. They agreed to cultivate the land, but countered that in devoting themselves to agriculture, they would have to renounce their Purohit Karma duties to give Karmkand, or religious rites. Their progeny, in turn, would never accept charity for their livelihood or act as religious functionaries. These Bhumihaars were then given the surname 'Tyagi' to acknowledge their renunciation.