ABSTRACT This article reports on a study that investigated the language learning and identity negotiation experiences of Japanese adults, nuclear immigrants, who left Japan and arrived in New Zealand after the 2011 Fukushima nuclear accident. Drawing on theories of investment, capital and communities of practice, the study explores how the nuclear immigrants negotiate their identities as L2 English learners and users within their New Zealand communities, both the L2 community and the L1 Japanese immigrant community infused with its own cultural and political ideologies. The study also asks why and how they invest or divest in English language learning and using practices. Data was collected via biographical narrative interviews from eight participants. Thematic narrative analysis identified themes which were interpreted in relation to dimensions of social activity represented by micro, meso, and macro levels. The findings indicate that the valuing and acceptance of the participants’ pre-existing capital serve as affordances to affirm and expand their identity, while rejection of their competence by sociocultural norms resulted in their withdrawal from the L2 communities, which eventually caused divestment in L2.