Ever since Papua New Guinea's independence in 1975, its relationship with the province of Bougainville has been troubled, with more than one attempt at secession. The linguistically and culturally diverse Bougainvilleans are themselves a microcosm of the extreme linguistic and cultural diversity of Papua New Guinea. Less than 5 per cent of the population and distinct from other Papua New Guineans mainly in terms of dark skin colour, they are concentrated geographically in a remote island group, offering no threat to other ethnic groups and not threatened by such groups elsewhere in Papua New Guinea. Both Bougainvillean ethnic identity and separatism are recent phenomena. The former emerged in the context of colonialism, which began in 1884. The politicisation of ethnic identity – the mobilisation of wide support based on identity in pursuit of political goals such as autonomy, increased government revenue and separation – began in the 1960s, in the context of both decolonisation and grievances against the colonial regime over the imposition of a massive mining project.

Because contextual factors are crucial to understanding how any particular ethnic conflict develops or is resolved, it is difficult to generalise from a single case. Nevertheless, the development within a short and recent time span of a politicised but divided ethnic identity, attempts to accommodate it with semi-federal arrangements and the subsequent development of violent separatist conflict offer insights into the dynamics of such phenomena. How does ethnic identity become politicised into separatist demands?