The advent of colonialism and its associated developments has been characterized as one of the most defining moments in the history of South Asia. The arrival of Christian missionaries has not only been coeval to colonial rule, but also associated with development in the region. Their encounter, critique, endeavour and intervention have been very critical in shaping South Asian society and culture, even where they did not succeed in converting people. Yet, there is precious little space spared for studying the role and impact of missionary enterprises than the space allotted to colonialism. Isolated individual efforts have focused on Bengal, Madras, Punjab and much remains to be addressed in the context of the unique region of the North East India. In North East India, for example, by the time the British left, a majority of the tribals had abandoned their own faith and adopted Christianity. It was a socio-cultural revolution.