This research focuses on the perception of the effects of smallpox on the demographic decline of the native North American populations by some English-speaking writers in the eighteenth century. It highlights the awareness expressed by contemporary observers of the circulation of new infectious diseases imported from Europe into North America, and of the effects of these diseases – of which smallpox is a critical but far from unique case – on the decimation or incipient extinction of native peoples. The aim of this research is to show how this awareness favoured, in English-speaking observers, the agglutination of the category of “European”, and an urgent need to document American human diversity before its disappearance. Works by John Lawson, John Brickell, James Adair, and Cadwallader Colden are considered before dwelling on the Lewis and Clark expedition and on Thomas Jefferson’s role in the expedition’s cultural aims and interests in medicine.
