The doctoral thesis examines the photographic technique of composite portraiture in relation to the works of Francis Galton and other protagonists of the technique in the context of the time of its invention in late nineteenth-century, as well as in current science, arts and popular culture. By starting with an exploration of the development as well as the epistemic nature, understanding, and reception of composite portraiture, the study aims to contextualise the photographic technique in nineteenth-century scientific and artistic discourses and analyse its controversial role as artificial construct and material evidence, as a prognostic tool and visual proof for physical, mental and social difference in the human species. The study reveals divergent but interlinked gazes, historically shaped lexi-visual regimes that have been adopted by composite portraiture as a socio-technological practice, which provide the organisational structure of the individual case studies in the different fields in which the technique has been used. My discussion of examples from this extensive corpus shows the pervasiveness and persistence of the technique in various fields as well as the adaptations, re-evaluations, and advancements of composite portraiture over its almost 150-year history. Composite portraiture is understood not only as a photographic technique of the superimpostion of several photographic portraits into an artificial meta-portrait in order to provide representative, stereotypical images of human features, but as an active agent and a (sometimes racist) ideologically motivated process in the formation of knowledge and social realities. The study aims to untangle the diverse interests, ideological backgrounds, experimental layouts, and the power-knowledge regimes that were involved in the formation of composite narratives and that became condensed into (highly charged) visual facial forms. Moreover, the examination demonstrates the proximity of the scientific technique to artistic photography and aesthetic theories. Thus its historical-epistemological approach can be described as a de-composition of the composite meta-portraits and of their discursive formation as typecasts for alleged social and biological groups of society. The investigation shows the connections of composite portraiture to earlier modes of “reading off the face” in physiognomy and phrenology; its involvement in criminology and criminalistics; the technique’s role in the medical field; as a diagnostic and predictive device and as a disciplinary technique of biopolitical management; its role in eugenics and its use as a normative ideal and visual target for a future society. Furthermore the technique was influential in a metaphorical and conceptual way: as a photo-visual re-enactment of visual modes of medical and scientific reasoning, as a conceptual aid in the development of theories of genetic transmission, and as a way of making sense of human perception and the formation of mental images. As artificial visualisations, they furthered a specific form of epistemological reasoning in which vision as the primary sense of evidential production was maintained – and complemented with an apparative hyper-visuality and new forms of photo-chemical perception. This first comprehensive study of composite portraiture examines the large corpus of historical composite portraits and individual component portraits, their production and contextualisation as well as the more recent production of composite portraits, often by digital means, in science, the arts, and popular culture. This diachronic reading of composite portraiture opens new perspectives on present uses of the technique but also on the historical images and their modes of reasoning, as well as on the role of composite photography in the construction of a particular epistemic picture of the human.