Research focusing on the political economy of Mississippian mound centers in the middle Savannah River valley has prompted a reevaluation of current interpretations regarding societal complexity. I conclude the clearest expression of classic Mississippian riverine-adaptation is evident at centers immediately below the Fall Line with their political ties to chiefdom centers in the Piedmont, and especially Etowah. By contrast, those centers on the interior Coastal Plain were politically autonomous with minimal signatures in social ranking. The scale of appropriated labor and resulting level of surplus production, necessitated by upland settlement on the Aiken Plateau, fostered social contradictions making communally-oriented and decentralized societies more sustainable than hierarchical forms.

A growing trend in Mississippian research in the archaeology of the southeastern United States stresses the need to shift away from categorizing generalizations (e.g., the concept of chiefdoms) that have been used to characterize Mississippi-period (A.D. 1000-1600) societies and advocates elucidating the unique occupational histories of Mississippian communities. This dissertation follows this trend with the goal of identifying and interpreting the particular historical and developmental trajectory of the Yon mound and village site (8Li2), a Fort Walton Mississippian site situated in the middle Apalachicola River valley, northwest Florida. Since its initial recording by Clarence Bloomfield Moore at the turn of the 20th century, Yon has been intermittently investigated by various researchers, but the data from these multiple investigations until now have been severely underreported or not reported at all. In this dissertation, these archaeological data from Yon are synthesized and used to identify the site's particular developmental history. The study proceeds through a careful examination of Yon's radiocarbon dates, artifact assemblage, platform mound construction, structural remains, and to a lesser extent, subsistence data, in an effort to tease apart its occupational components and contextualize them within the wider Fort Walton and Mississippian milieu. To this end, particular attention is given to the wider Fort Walton manifestation of the Apalachicola-lower Chattahoochee River valley and the Rood and later Lamar Mississippian regional variants that were located upriver from Yon in the upper reaches of the lower Chattahoochee River valley. This study demonstrates that Yon emerged rather precipitously as a Middle Fort Walton period center circa A.D.1200, a time marked by initial mound construction and the first intense village occupation at the site, which was preceded only by a very small, pre-Fort Walton, Swift Creek occupation there around A.D. 320. Probable antecedent events at a nearby Fort Walton mound center, Cayson (8Ca3), as well as contact with Rood Mississippian groups to the north are hypothesized as influencing Yon's Middle Fort Walton development and florescence. Evidence indicates that this initial Middle Fort Walton occupation was followed by an occupation of Lamar groups. Regional data and radiocarbon evidence from Yon suggest that this Lamar component likely began during protohistoric times (circa A.D. 1600) and continued into the late seventeenth to early eighteenth centuries. It is hypothesized that this Lamar occupation was the result of Lamar groups migrating down the lower Chattahoochee-Apalachicola River in the wake of European contact. As a whole, this study represents the most complete documentation of the occupational history of any Fort Walton mound center to date. As such, it can provide an important foundation for future studies of Fort Walton mound centers and sites in the Apalachicola-lower Chattahoochee River region.