This paper employs concepts from Bourdieu’s theory of social fields and contemporary research on transnationalism to explore the complicated history of population movement, culture contact, and interaction that fueled the origins of Mississippian society in the greater Cahokia area and closely related socio-political developments in the Central Illinois River Valley (CIRV) of west-central Illinois. We offer a new take on Mississippian origins and the history of culture contact in the CIRV, arguing that interregional simulta- neity and inter-group collaboration played an important part of the early processes of Mississippianization in the North American Midwest. By decentering Cahokia in our explanation of Mississippian origins in the greater Midwest, we argue for a long-term persistence of traditional pre-Mississippian practices in the CIRV region, beginning with the first documented engagement among Cahokians and Illinois Valley groups in the early eleventh century until the beginning of the thirteenth century AD.