Western medicine was utilized as an instrument of empire in colonies established by conquest, occupation, and settlement and was practiced on American Indians between 1797 and 1871. This was medicine in the agents, knowledge and processes of western physicians, western medical "advances" and western medical practices that became part and parcel of the disease experiences of Native Americans and developing federal health care policies. Western medicine, in the form of imperial medicine, was political, economical, military and racial in nature and served to legitimize a federal presence in north American Indian communities.
Physicians, missionaries, politicians, traders and the United States army employed western medicine to exacerbate expansion of the United States and the "civilization" of the American Indian. Practitioners of secular western medicine presumed that biomedicine was superior to all other forms of medicine as they attempted to eradicate Native American health care practices. Proponents of western medicine controlled access to western medical benefits, denigrated American Indian women, and misinterpreted American Indian responses to epidemic diseases. The diseases most often carried into Indian Country during western expansion were smallpox, cholera, syphilis and gonorrhea. Federal vaccination efforts, medical benefits treaties, traders' and the military's efforts to contend with these diseases played a central role in the development of the Imperial medical model. Native Americans accepted western medical practices when they were found effective or refused those considered untimely, or inappropriate as they cared for themselves and each other.