This thesis explores the life history of six isolated skulls interred in Mound 3 of the Elizabeth site, a Middle Woodland site in the lower Illinois valley. This study employs analyses of osteological features, stable and radiogenic isotopes, and biodistance for a cross-section of the Mound 3 population (n=15), including the isolated crania. Isotopic results reveal significant variation in lead isotope ratios in enamel, and interpretively meaningful variation in strontium values. However, bone carbonate oxygen values are not significantly different. Carbon isotope values from bone carbonate revealed only sex-based dietary differences. Biodistance data indicate relatively genetic homogeneity at the site, although significant variation was present in two of the isolated crania. Ultimately, data indicate that two of the six isolated skulls likely originated from elsewhere in the valley, but that the population likely resided in the Elizabeth site vicinity in the decade preceding death, and were not outsiders.