The Missing Majority: Rethinking Bilingualism Research from Nigeria and the Non-WEIRD World

Bilingualism research has significantly advanced our understanding of language control, cognitive flexibility, and multilingual competence. However, much of this knowledge has emerged from populations located in Western, Educated, Industrialized, Rich, and Democratic (WEIRD) societies, where bilingualism often exists as an institutionalized, additive, and compartmentalized phenomenon. This paper argues that such a concentration has produced theoretical models that risk overgeneralizing from sociohistorically specific linguistic experiences. Drawing on Nigeria as a representative case of high-density multilingualism, this paper examines how multilingual practices in non-WEIRD contexts challenge dominant assumptions about language boundaries, language switching, and cognitive control. In Nigeria, multilingualism is often necessity-driven, socially embedded, and dynamically negotiated across fluid linguistic repertoires involving indigenous languages, colonial languages, and contact varieties such as Nigerian Pidgin. These realities complicate bounded-language models that continue to shape mainstream psycholinguistic inquiry. Rather than treating African multilingualism as peripheral or exceptional, this paper positions it as central to the future development of ecologically valid theories of bilingualism. It concludes by advocating for a broader, decolonial, and context-sensitive science of multilingualism capable of accounting for the linguistic realities of the global majority.