J. Johnstone has revealed the historical truth that towards the middle of the 18th century a Hindu revivalist movement took place in the East of India. The conversion to Hinduism on the Eastern Frontier from Sadiya down to Chittagong was daily taking place. To quote him “A man belonging to Hill tribes, if the Raja chose at any time, received the sacred thread of twice born castes, and on payment of small sum of money was admitted as a Hindu and was thenceforth called Khetree (probably a corruption of Khatri). This privilege was not accorded to Mussulmans. I once asked a Manipuri why they received hill-men and not Mussalman, both being Mlecchas according to Hindu theory, he said it was because the hill-men had sinned in ignorance whereas Musulmans knew the evil of their ways."
- Historical Researches into Some Aspects of the Culture…