The British Nationality Act (BNA) of 1948 was designed to provide a form of supranational citizenship to accommodate the separate nationality provisions that were beginning to proliferate as a result of constitutional change within the late empire, decolonization and the formation of the Commonwealth. Under the provisions of the BNA, members of the Commonwealth would continue to be unified by transnational forms of citizenship, at least in principle. The Act aimed to cover every political arrangement conceivable in the late empire and early Commonwealth and contributed to the transformation of Great Britain into a multicultural society, by providing the legal vehicle for immigration into the UK in the second half of the twentieth century. However, the BNA had its limits. It could not be applied to territories characterized by constitutional exceptionalism and jurisdictional hybridity. In the Condominium of the New Hebrides, jointly governed by France and Great Britain from 1906 to 1980, the majority of the indigenous population were unable to benefit from the BNA, despite efforts to extend its coverage in all eligible territories. As part of the condominium agreement, the indigenous population were ineligible for any form of citizenship-British, French or New Hebridean-and remained stateless until independence as the Republic of Vanuatu in 1980. This article examines the relationship between indigenous statelessness and the BNA, exploring the implementation, interpretation and extent of the BNA in a territory characterized by constitutional hybridity, compromise and ambiguity. It argues that despite its emphasis on universal commonwealth citizenship, the BNA could not accommodate the diverse political, legal and constitutional diversity that characterized the Dominions, Crown Colonies, protectorates, protected states and condominia that had proliferated under imperial rule and whose legacies continued to inform the possibilities for decolonization and the politics of post-colonial citizenship making.