After Cahokia: Indigenous Repopulation and Depopulation of the Horseshoe Lake Watershed AD 1400-1900. White et al. 2020

The occupation history of the Cahokia archaeological complex (ca. AD 1050–1400) has received significant academic attention for decades, but the subsequent repopulation of the region by indigenous peoples is poorly understood. This study presents demographic trends from a fecal stanol population reconstruction of Horseshoe Lake, Illinois, along with information from archaeological, historical, and environmental sources to provide an interpretation of post-Mississippian population change in the Cahokia region. Fecal stanol data indicate that the Cahokia region reached a population minimum by approximately AD 1400, regional population had rebounded by AD 1500, a population maximum was reached by AD 1650, and population declined again by AD 1700. The indigenous repopulation of the area coincides with environmental changes conducive to maize-based agriculture and bison-hunting subsistence practices of the Illinois Confederation. The subsequent regional depopulation corresponds to a complicated period of warfare, epidemic disease, Christianization, population movement, and environmental change in the eighteenth century. The recognition of a post-Mississippian indigenous population helps shape a narrative of Native American persistence over Native American disappearance.

File: White-et-al.-2020-after_cahokia_indigenous_repopulation_and_depopulation_of_the_horseshoe_lake_watershed_ad_14001900.pdf

An Evaluation of Fecal Stanols as Indicators of Population Change at Cahokia, Illinois. White et al. 2018

Fecal stanols deposited in sediment provide evidence of trace human waste products and have been proposed as a proxy for measuring population change. Despite its potential to contribute to paleodemographic studies, the method has not been evaluated against conventional archaeological population reconstructions to determine its fidelity in identifying changes in ancient populations nor has it been applied in an environmental setting outside of the Arctic, where low temperatures enhance stanol preservation. We studied sediment cores recovered from a lake adjacent to Cahokia, the largest and most well-studied prehistoric mound center in North America. We found fecal stanol data closely track independently established population reconstructions from multiple sources, confirming the utility of the method and demonstrating its viability in temperate climates.

File: White-et-al.-2018-Fecal-Stanols-at-Cahokia-Journal-of-Archaeological-Science.pdf

Fecal Stanols Show Simultaneous Flooding and Seasonal Precipitation Change Correlate with Cahokia’s Population Decline. White et al. 2019

A number of competing hypotheses, including hydroclimatic variations, environmental degradation and disturbance, and sociopolitical disintegration, have emerged to explain the dissolution of Cahokia, the largest prehistoric population center in the United States. Because it is likely that Cahokia’s decline was precipitated by multiple factors, some environmental and some societal, a robust understanding of this phenomenon will require multiple lines of evidence along with a refined chronology. Here, we use fecal stanol data from Horseshoe Lake, Illinois, as a population proxy for Cahokia and the broader Horseshoe Lake watershed. We directly compare the fecal stanol data with oxygen stable-isotope and paleoenvironmental data from the same sediment cores to evaluate the role of flooding, drought, and
environmental degradation in Cahokia’s demographic decline and sociopolitical reorganization. We find that Mississippi River flooding and warm season droughts detrimental to agriculture occurred circa (ca.) 1150 CE and possibly generated significant stress for Cahokia’s inhabitants. Our findings implicate climate change during the Medieval Climatic Anomaly to Little Ice Age transition as an important component of population and sociopolitical transformations at Cahokia, and demonstrate how climate transitions can simultaneously influence multiple environmental processes to produce significant challenges to society.

File: PNAS-2019-White-et-al.-1809400116.pdf

Evidence for Paleoindians In Wisconsin and at the Skare Site. Schroeder 2007.


Sissel Schroeder
2007 Evidence for Paleoindians In Wisconsin and at the Skare Site. Plains Anthropologist 52(201):63-91.

The Skare site, situated along the Yahara River in southern Wisconsin, has produced evidence of human activity spanning from Paleoindian times to the early Euro-American settlement of Wisconsin. During recent excavations at the site, two Paleoindian artifacts, the base of a Folsom biface and a heavily reworked Dalton biface, were found below the plow zone. Inventories of Paleoindian sites and fluted biface distributions primarily documented in the surface archaeology of Wisconsin are examined to establish a regional settlement context for the Skare site and to investigate the nature of Paleoindian exploration and colonization of the state. Areas with the highest numbers of known Paleoindian sites and reported fluted bifaces correspond with resource-rich habitats, unique lithic raw material sources, and regions that have been the focus of Paleoindian research and fluted biface collecting. Clovis bifaces are found across the state, while Folsom bifaces are largely restricted to the southern half of the state. A comparison of Early and Late Paleoindian site distributions indicates that Paleoindian exploration of the state occurred relatively rapidly following the last glacial retreat.

Cahokia’s emergence and decline coincided with shifts of flood frequency on the Mississippi River. Munoz et al. 2015


Samuel E. Munoz, Kristine E. Gruley, Ashtin Massie, David A. Fike, Sissel Schroeder, and John W. Williams
2015 Cahokia’s emergence and decline coincided with shifts of flood frequency on the Mississippi River. Proceedings of the National Academy of Science 112(20):6319–6324.


Our paper evaluates the role that flooding played in the emergence and decline of Cahokia—the largest prehistoric settlement in the Americas north of Mexico that emerged in the floodplain of the Mississippi River around A.D. 1050. We use sediment cores to examine the timing of major Mississippi River floods over the last 1,800 y. These data show that Cahokia emerged during a period of reduced megaflood frequency associated with heightened aridity across midcontinental North America, and that its decline and abandonment followed the return of large floods. We conclude that shifts in flood frequency and magnitude facilitated both the formation and the breakdown of Cahokia and may be important factors in the declines of other early agricultural societies.


Here we establish the timing of major flood events of the central Mississippi River over the last 1,800 y, using floodwater sediments deposited in two floodplain lakes. Shifts in the frequency of high-magnitude floods are mediated by moisture availability over midcontinental North America and correspond to the emergence and decline of Cahokia—a major late prehistoric settlement in the Mississippi River floodplain. The absence of large floods from A.D. 600 to A.D. 1200 facilitated agricultural intensification, population growth, and settlement expansion across the floodplain that are associated with the emergence of Cahokia as a regional center around A.D. 1050. The return of large floods after A.D. 1200, driven by waning midcontinental aridity, marks the onset of sociopolitical reorganization and depopulation that culminate in the abandonment of Cahokia and the surrounding region by A.D. 1350. Shifts in the frequency and magnitude of flooding may be an underappreciated but critical factor in the formation and dissolution of social complexity in early agricultural societies.


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Identifying American native and European smelted coppers with pXRF: a case study of artifacts from the Upper Great Lakes region. Dussubieux and Walder 2015.


Dussubieux, Laure and Heather Walder
2015 Identifying American native and European smelted coppers with pXRF: a case study of artifacts from the Upper Great Lakes region. Journal of Archaeological Science 59:169-178.

In North America, it is critical for archaeologists to differentiate between American native copper and European smelted copper. Indeed, native copper, a rather pure metal, was not smelted in this region, unlike European copper objects that later became available to Native Americans during trading encounters. Until now, archaeologists with a low budget wishing to use a totally non-invasive approach have relied on visual inspection and archaeological contextualization of the objects to distinguish American native copper from European smelted copper. This paper assesses the reliability of portable x-ray fluorescence (pXRF) as a fast, effective, and completely non-destructive method of differentiating the two types of copper present at Northern American sites through a case study of two sites from the Upper Great Lakes region. To establish group attribution with pXRF, results obtained on a subset of objects with LA-ICP-MS are used. Results indicate that for the specific purpose of differentiation between native and European copper types, pXRF can be used reliably, without sample preparation and despite surface corrosion. Therefore, pXRF provides a non-destructive way to clarify European trade item distribution and continuity of native copper object use among Indigenous peoples of North America during the colonial period.


Defining the Spatial Patterns of Historical Land Use Associated with the Indigenous Societies of Eastern North America. Munoz et al. 2014.


Munoz, Samuel E, David J Mladenoff, Sissel Schroeder, and John W Williams
2014 Defining the Spatial Patterns of Historical Land Use Associated with the Indigenous Societies of Eastern North America. Journal of Biogeography 41(12):2195–2210.

Aim To review and synthesize multiple lines of evidence that describe the spatial patterns of land use associated with prehistoric and early historical Native American societies in eastern North America in order to better characterize the type, spatial extent and temporal persistence of past land use.

Location Temperate forests of eastern North America, and the Eastern Wood- lands cultural region.

Methods Ethnohistorical accounts, archaeological data, historical land surveys and palaeoecological records describing indigenous forms of silviculture and agriculture were evaluated across scales ranging from local (100 km) to regional (102 km) to produce a synthetic description of land-use characteristics.

Results Indigenous land-use practices created patches of distinct ecological conditions within a heterogeneous mosaic of ecosystem types. At all scales, patch location was dynamic, and patches underwent recurrent periods of expansion, contraction and abandonment. Land-use patches varied in their extent and persistence, and are broadly categorized as silvicultural (management of undomesticated woodland taxa) or agricultural (cultivation of domesticated taxa). Silvicultural patches persisted for centuries and extended kilometres to tens of kilometres around settlements and travel corridors. The dynamics of agricultural patches varied among groups, with persistence ranging from decades to centuries and extent ranging from less than a kilometre to tens of kilometres around settlements. Beyond patch boundaries, human impacts on ecosystems become indistinguishable from other drivers of environmental heterogeneity. These characteristics of patches are evident across scales and multiple lines of evidence.

Main conclusions Our findings challenge the view that prehistoric human impacts on vegetation were widespread and ubiquitous, and build on previous work showing these impacts to be more localized and heterogeneous by providing quantitative descriptions of land-use patch characteristics. Collaborative efforts that combine multiple data sources are needed to refine these descriptions and generate more precise measures of land-use pattern to further investigate the history of human impacts on the Earth system.


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Stylistic and Chemical Investigation of Turqoise-Blue Glass Artifacts from the Contact Era of Wisconsin. Walder 2013.


Walder, Heather
2013 Stylistic and Chemical Investigation of Turqoise-Blue Glass Artifacts from the Contact Era of Wisconsin. Midcontinental Journal of Archaeology 38(1):119-142

Typologically and visually similar glass trade beads, found on many archaeological sites of Native and French interaction in Wisconsin dating to the seventeenth and eighteenth centuries, often vary in chemical composition. These chemical differences likely indicate both fluctuating technological processes in European glass “recipes” and changes related to suppliers of trade goods to North America. To investigate regional differences among bead compositions, 87 turquoise-blue glass beads and 2 remelted glass pendants from five different seventeenth-century and early-to-mid-eighteenth-century sites in present-day Wisconsin were analyzed nondestructively using Laser Ablation–Inductively Coupled Plasma–Mass Spectrometry (LA-ICP-MS). The different glass recipes can be divided into chemical subgroups that reflect both the chronological period assigned to the archaeological site and the geographic proximity of sites. The analysis reveals details about the exchange of trade goods and the dynamic population movements that are characteristic of this period of interaction among locally indigenous groups, Native newcomers to the region, and arriving Europeans.


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An investigation of the origins of variation in perishable architecture at Jonathan Creek. Schroeder 2011.


Schroeder, Sissel
2011 An investigation of the origins of variation in perishable architecture at Jonathan Creek. Southeastern Archaeology30(2):311–336

The Jonathan Creek site in Kentucky was excavated in the early 1940s in an effort to uncover the community plan of an entire Mississippian town and mound center. Although the project terminated prematurely, the remnants of 89 structures representing a diverse array of architectural foundation styles were documented. Quantitative and qualitative analyses of multiple attributes, such as posthole diameter and spacing, wall-trench width and depth, roof supports, and floor area, are necessary to adequately parse the variation in architectural style, construct inferences about the above- ground appearance of buildings, and suggest origins for the diverse construction methods used at the site. At least some of the distinctive differences in foundation preparation would have resulted in diversity in the appearance of finished buildings. Time is not wholly adequate to explain this diversity. Technological and functional choices made by the ancient builders account for some of this variation, while social, genealogical, and ethnic differences, and possibly distinctive ritual customs and traditions among the resi- dents, explain other sources of variation.


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