Although there was not a focused administration on ethnic minorities in Finland until the last decades of the 20th century, there was variety of rationalities, techniques and practices of governance used for their conduct. In this article I analyze how the governance of the Roma and the Sámi – two biggest minorities at the time – changed after mid-1800s, when the new understanding, the ethno-cultural one, on population diffused among administration and governing bodies. This Foucauldian analysis concentrates on the descent of this ‘event’, the social and political conditions of its mergence, and the actual changes it meant in the governance of these minorities.