India’s frontiers were areas of extraordinary human interest for agents of empire and men of science throughout the nineteenth century. This chapter investigates the production, dissemination, and reception of British knowledge of frontier inhabitants. Widespread recognition among personnel in colony and metropole alike that frontier people were important did not, however, emanate from or lead to settled knowledge of their origins or significant characteristics. Doubts over the validity of particular informants and modes of representation, disputes over competing theoretical frameworks, and controversies over the nature of frontier communities were at the heart of colonial ethnography. Frontier ethnography was a diverse field with complex relations to state power. Examining sketches and photographs as well as written material, the chapter demonstrates how processes of reproduction, adaptation, and circulation generated influential but highly unstable knowledge of human diversity.