According to Hindu scriptures, the term Ambastha refers to the offspring of a Brahmin father and a Vaishya mother, whose traditional occupation was the practice of medicine.
They have been described as inhabitants of northwestern part of Indian subcontinent (near Lahore), and they were conquered by Nakula and paid tribute to Yudisthira.
[1] Citing the Hindu text Parasara, Leslie mentions that the Ambastha is supposed to treat the Brahmins only, and hence considered as "a clean caste, definitely below the brahman, but certainly well within the twice-born group".
[5] According to Bindeshwari Prasad Sinha the ancient Ambasthas migrated to Bihar and created a sub-division of the greater Kayastha caste of this region.
Bharatmallik (17th century), the author of the Chandraprabha and Bhattitika has introduced himself as both Vaidya and Ambashtha, which indicates both the castes may have been considered as one in early medieval Bengal.