In 1909, curator Charles-Edward Winslow established a department of public health in New York City's American Museum of Natural History (AMNH). Winslow introduced public health as a biological science that connected human health-the modern sciences of physiology, hygiene, and urban sanitation-to the natural history of plants and animals. This was the only time an American museum created a curatorial department devoted to public health. The AMNH's Department of Public Health comprised a unique collection of live bacterial cultures-a "Living Museum"-and an innovative plan for 15 exhibits on various aspects of health. I show how Winslow, facing opposition from AMNH colleagues, gathered scientific experts and financial support, and explain the factors that made these developments seem desirable and possible. I finish with a discussion of how the Department of Public Health met an abrupt and "inglorious end" in 1922 despite the success of its collections and exhibitions.