This paper analyses some key historical developments (from early twentieth century to present) in Bangladesh from a socio-historical and language ideological perspective to explore the social injustice faced by the non-dominant and linguistically diverse population. These developments sparked language debates involving questions of identity, nationhood, and political hegemony. The Bengal partition in 1905, for example, flared up the Bengali monolingualism and the territorial principle so strongly that the British had to give in, putting the non-dominant Bengali-speaking Muslims at a socio-economic disadvantage. The 1947 partition brought to the forefront the ideologies of an Islamic language, a Hindu language, and linguistic diversity as a threat to national unity, making both the Bengali-speaking Muslims and the hill people face social and political injustice. The birth of Bangladesh in 1971 was a welcome change but its monolingual Bengali ideology put the speakers of minority languages at a long-term disadvantage. The 1997 Peace Accord, UNESCOS's 1999 declaration of 21 February as the International Mother Language Day, the 2010 educational policy, and the creation of an International Mother Language Institute offered some flickers of hope, but the underlying ideology remains Bengali monolingual, still creating barriers for a socially just future for minority language speakers.