Time and Archaeological Traditions in the Lower Illinois Valley

The issue of time remains a crucial one in Lower Illinois Valley archaeology, and key problems remain unresolved. In this paper, new radiocarbon assays and published dates are used to test hypotheses concerning intra-site bluff top mound chronologies, timing and structure of valley settlement, and the emergence of regional symbolic communities during the Middle Woodland period (ca. 50 cal B.C.-cal A.D. 400). We show that within sites Middle Woodland mounds were constructed first on prominent, distal bluff ridges and subsequently in less-visible spaces, though additional dates are needed to fully understand intra-site chronology. Our analyses generally support previous studies suggesting a north-to-south settlement trajectory of the valley, though habitation site dates indicate a more complicated pattern of regional occupation that has yet to be fully explicated. In addition, floodplain regional symbolic communities also emerged along a north-to-south pattern, though not as rapidly as bluff crest mounds. Importantly, results indicate future areas of research necessary to elucidate regional chronology, resettlement of the valley, and community interactions.