This paper focuses on the relation between state policies and ethnicisation in the borderland of Bengal. On the basis of a case study of the lowland Garos of Bangladesh, the paper argues that attempts by the successor states of Bengal, East Pakistan and Bangladesh to 'other', and even 'exclude', the Garos have significantly impacted on Garo self-perception and organisation, resulting in the formation of a close-knit ethnic community. The paper focuses on three twentieth-century episodes in the lives of the lowland Garos. The first is the 1936 British administrative reorganisation of Mymensingh District which resulted in the emergence of a notion of a separate Garo homeland in Bengal. The second is the mass exodus of Garos across the international border into the Indian hills which took place in 1964. This traumatic experience pushed the Garos to unify. The third is the Independence War of 1971 and the birth of Bangladesh. All three episodes are directly related to state policies which excluded the Garos (as well as the neighbouring minorities) from the dominant discourse of Bengali/Bangladeshi citizenship. The paper concludes that the Garos of Bangladesh are a close-knit ethnic community - not in spite of these state attitudes - but rather as an outcome of them.