The study of identities struggles to capture the moments and dynamics of identity change. A crisis moment provides a rare insight into such processes. This paper traces the political identities of the inhabitants of a region at war – the Donbas – on the basis of original survey data that cover the four parts of the population that once made up this region: the population of the Kyiv-controlled Donbas, the population of the self-declared “Donetsk People’s Republic” and “Luhansk People’s Republic,” the internally displaced, and those who fled to the Russian Federation. The survey data map the parallel processes of a self-reported polarization of identities and the preservation or strengthening of civic identities. Language categories matter for current self-identification, but they are not cast in narrow ethnolinguistic terms, and feeling “more Ukrainian” and Ukrainian citizenship include mono- and bilingual conceptions of native language (i.e. Ukrainian and Russian).