The purpose of this study is to conduct a comparative analysis of the vulnerability of languages by examining actual language usage in order to assess the socio-cognitive impact that the status of a language can have on its speakers. For this purpose, we have chosen four Tibeto-Burman languages— each with a different status with regard to language endangerment—spoken in two North Eastern states of India. Of the four languages, two are spoken in Assam viz: Bodo (a Scheduled Language and an associate official language of Assam) and Garo (an associate official language in Meghalaya and with speakers also in Assam). The other two languages chosen for this study are Miju and Digaru: both endangered languages, primarily spoken in the Lohit and Anjaw districts of Arunachal Pradesh neither of which have any official recognition in any part of the state. The vulnerability of these languages is investigated in relation to their status from two vantage points: (a) the functionality of language and (b) the political question of representation. This study wishes to emphasize the critical nature of mother tongue transmission from one generation to another, as the declining use of these languages has a significant impact on language ecology, identity, heritage and the associated knowledge system. The current study elaborates on the endangered status of indigenous languages from multiple perspectives in order to raise multilevel concerns spanning from socio-cultural to cognitive while addressing the political question of linguistic identity of each chosen community in two North Eastern states of the nation of India. Thus, Bodo and Garo are studied in context of their status and functionality in contrast to Assamese (perceived as the dominant language of Assam spoken by the majority) while the endangerment threat posed to Miju and Digaru, despite being indigenous languages, are studied in the context of the near irreversible rise of Hindi as the lingua franca of the state.