Establishing a Strontium Isoscape for the American Midcontinent: Who were Cahokia’s Immigrants?

Strontium isotope values (87Sr/86Sr) are used to study prehistoric human population movement worldwide. Archaeological research in the Midwest has highlighted the importance of population movement in promoting cultural and sociopolitical change. For example, our earlier strontium (87Sr/86Sr) isotope research identified one-third of Cahokia’s inhabitants as immigrants. Locating the homelands of these immigrants has remained problematic due to the lack of regional strontium data. In this presentation we report on new 87Sr/86Sr data derived from fauna from Minnesota to Mississippi that creates the first regional strontium ‘isoscape’ map to guide the identification of potential places of origin for Cahokia’s immigrants.