This paper examines how Koreans became industrial workers in the first and second phases of industrialisation on the peninsula: under Japanese colonial rule, 1931-1945, and under the DPRK's post-Korean War heavy industrialisation, 1953-1960. While the political regimes of the Japanese colony and postcolonial DPRK were different, industrialisation occurred under similar conditions, characterised principally by war, state-led development and imperialism. Processes of proletarianisation also reveal similarities in the two periods, including the widespread use of forced mobilisation and immobilisation of workers and a bureaucratic apparatus supporting close control of labour. In addition to illuminating the lesser-known origins of industrial modernity on the Korean peninsula, this paper contributes of the critique of conventional views about the role of 'free wage labour' under developing capitalism.