Paleoanthropology emerged as a field of research in the 1860s, in response to the discovery of fossilized human bones. Darwin had already proposed his theory of evolution, and some scientists interpreted the recently discovered human fossils within the context of human evolution. However, influential anthropologists, especially in France, who were among the first to study these human fossils and were instrumental in establishing this new field of paleoanthropology, relied upon pre-existing methods and ideas drawn from the anthropological study of Neolithic and Bronze Age skeletons conducted during the mid-nineteenth century. This chapter argues that during this early phase of paleoanthropology, from the 1850s to the 1880s, a methodological and theoretical framework used by anthropologists to study prehistoric human skeletons was extended to the study of even earlier Paleolithic skeletons from the Pleistocene. This methodological and theoretical framework was based upon the craniometric and anthropometric measurement of Paleolithic skeletons in order to identify distinctive “fossil human races,” combined with the widely held idea that during the prehistoric period populations of racially distinct humans had migrated into Europe at different times. For these early paleoanthropologists, their task was to apply anthropological research methods to the analysis of Pleistocene human fossils in order to identify their race and then to trace the changes in the races that inhabited Ice Age Europe. As a result of discoveries and scientific developments occurring during the 1880s and 1890s, paleoanthropology shifted away from this framework and increasingly adopted methods and theories that emphasized the phylogenetic and evolutionary study of extinct hominid species.