This paper intends to study how the religiouscommunity is determined by the geographicalexpression and by the political boundary. Incolonial Indian census, there was a category of tribalreligion which disappeared after political freedom ofIndia. All non- Muslim and non Christian tribals wereassumed as a Hindu in post colonial census. Theassimilation of the faith of minority by the religiousmajority through the imagined political boundary or socalled the national movement is part of my researchendeavour. I will try to figure out how the politicalboundary became a determining force in reconstructinga religious community or how the faith of tribals wasreplaced by Hinduism. In this paper I will focus on twotribes of Chotanagpur i.e. Munda and Oraon. How thefaith of tribal in general and the religion of Mundas andthe Oraons in particular got changed through theconcept of Indianisation will be the key point ofdiscussion in this paper. It would be interesting to knowhow far the dominant majoritarian politics of Hinduismincorporated and assimilated the tribal faith intoHinduism through the ‘imagined native religion’ whichperhaps was none other than Hinduism.