This translation of Pauline Tarnowsky’s Les Femmes Homicides presents an important historical work in English for the first time. Tarnowsky, a neuropathologist and one of the first women permitted to attend medical school in Russia, has often been referred to as the “first female criminologist.” In Les Femmes Homicides, she analyzes data collected from a sample primarily composed of rural peasant women, 160 convicted of homicide and a control group of 150 non-criminal women, to examine the relative influence of the “born criminal” theory often associated with Cesare Lombroso, heredity, and the social contexts experienced by women convicted of homicide. Part I of the text outlines Tarnowsky’s methodology and introduces some of the first motivational categories for women’s homicidal behavior. Part II expands on these categories and further explores the relative importance of causal factors related to biology and social conditions. Her meticulous methodological attention to the intersections of race, environment, time, place, unity, and other social conditions makes this one of the earliest, and still one of the most comprehensive, studies of female homicide offenders. Tarnowsky draws comparisons between carefully matched criminal and non-criminal populations and employs what we would now recognize as social-scientific reasoning to study and explain homicides committed by women. Ultimately, she challenges and rejects Lombroso’s theory of “born criminals.” This historical work, and its influence on the development of criminological theory, remains essential reading for scholars and students of criminology, homicide studies, social history, gender studies, theory development, the history of ideas, law and criminology, and the social study of science.