This article considers understandings of ‘Britishness’ in the Natal colony in the 1870s. Focusing on St Helenian children’s expulsion from ‘government’ schools that were ostensibly open to all racial groups, the article shows how competing definitions of race and ‘Britishness’ shaped the responses of colonial officials, settlers and the St Helenian community to the expulsion. The white settler population in Natal was concerned about St Helenian economic migrants’ inclusion in white, English society. In particular, the ambiguous racial status of St Helenians was seen as potentially harmful to white children. The focus on a group of recent incomers to the colony uncovers a process of racialisation unfolding in the context of migrations within the British Empire. The case highlights how movement and migration within the empire could bring these definitions of race and Britishness into conversation and conflict with each other.