Despite its tiny size and population, Brunei Darussalam is linguistically and ethnically diverse. The dominant race, the Malays, is made up of seven different ethnic groups, namely Belait, Bisaya, Brunei Malays, Dusun, Kedayan, Murut and Tutong, all of whom are considered indigenous to Brunei. With the exception of the Brunei Malays and Kedayans, each of the other groups traditionally speaks their own distinct indigenous languages that are distinct from the Malay language. Drawing on qualitative data obtained through interviews and documentary analysis, this study aims to explore the historical and contemporary interrelationships between these languages within the 'ecology of language' framework, and to find out how the notion of linguistic diversity interplays with national unity in the face of modernization. Although the study reveals a high level of tolerance by the informants toward linguistic diversity, there is evidence to suggest that as the minority ethnic population are abandoning their traditional languages and shifting to Malay, a synchronous convergent evolutionary process of identity shift is occurring too. The implications are that as linguistic diversity is diminishing in Brunei, so too is cultural diversity.