Dr. Thomas E. Emerson and Dr. Kristin M. Hedman from the Illinois State Archaeological Survey-Prairie Research Institute at the University of Illinois present a new case for Cahokia's demise. The new theory was published in Southern Illinois University Press' volume, Beyond Collapse: Archaeological Perspectives on Resilience, Revitalization, and Transformation in Complex Societies. Emerson and Hedman contributed a chapter to the volume entitled, The Dangers of Diversity: The Consolidation and Dissolution of Cahokia, Native North America's First Urban Polity, that explores internal divisions that led to the collapse of Cahokia.
The archaeologists claim internal conflict by social, political, ethnic, and religious factions are a more reasonable description of events that led to Cahokia's collapse than environmental causes, as is the popular theory. They present new bioarchaeological evidence that demonstrates that as many as one-third of the Cahokian residents were immigrants and that these immigrants likely represented groups that were culturally, ethnically, and perhaps linguistically distinct from local populations. Emerson clarifies further,