Bunyore, like the rest of present-day Western Province of Kenya, came under British administration as part of the Eastern Province of the Uganda Protectorate between 1890 and 1895. The argument of this thesis is that if this development drew the AbaNyole into the world capitalist nexus, it also created conditions within which an expanding nineteenth-century social field of action was confronted with new diseases and ideas about these diseases that were extremely important in the transformation of the 'Nyole medical landscape during colonialism. This transformation took place within the framework of a British colonial medical science that defined itself within and above 'Nyole cosmology, and a British racial temperament that defined Bunyore as an epidemiological landscape. Both were normal requirements for colonial self-definition, cultural positioning, and boundary-marking between 'science' and 'tradition', 'culture' and 'nature'. This is why discourses on disease and medicine during the first two decades of colonialism revolved around the idea of nature, an idea that was a rendering of not just the physical, natural characteristics, of the colony, but also of the colony's inhabitants. Based on a bifocal address and the prevalence of argument by negative contrast, the image of the 'natural' was used to not only constitute the intellectual domain within which knowledge, strategies, policies, and justifications for domination were fashioned, but also expropriate AbaNyole's capacity to narrate their own bodily experiences. This was a dual process that created fertile grounds in which ideas about Western biomedicine and its technologies were nurtured and debated by the AbaNyole. The outcome of these debates, together with contradictions within colonial medical policies, led, from the mid 1930s onwards, to the systematization of the Health Center as an arena in which a new object of knowledge, Bora Afya (Good Health), and field of intervention, the African home, were constituted. This was a transition from preventive to curative medicine, political to social medicine.