This thesis is an analysis of the production of assimilation discourse, in terms of Aboriginal people’s and white people’s social relations, in a small selection of popular fiction texts from the 1950s and 1960s. I situate these novels in the broader context of assimilation by also undertaking a reading of three official texts from a slightly earlier period. These texts together produce the ambivalent white Australian story of assimilation. They illuminate some of the key sites of anxiety in assimilation discourses: inter-racial sexual relationships, the white family, and children and young adults of mixed heritage and land ownership. The crux of my argument is that in the 1950s and early 1960s the dominant cultural imagining of Australia was as a white nation. In white discourses of assimilation to fulfil the dream of whiteness, the Aboriginal people – the not-white – had to be included in or eliminated from this imagined white community. Fictional stories of assimilation were a key site for the representation of this process, that is, they produced discourses of ‘assimilation colonization’. The focus for this process were Aboriginal people of mixed ancestry, who came to be represented as ‘the half-caste’ in assimilation discourse. The novels I analyse work as ‘conduct books’. They aim to shape white reactions to the inclusion of Aboriginal people, in particular the half-caste, into ‘white Australia’. This inclusion, assimilation, was an ambivalent project – both pleasurable and unsettling – pleasurable because it worked to legitimate white colonization (Aboriginal presence as erased) and unsettling because it challenged the idea of a pure ‘white Australia’.