Abstract
This book examines the impacts of climate on prehistoric cultures in North America. Specifically, William Foster uses historic information on climate and culture changes in Europe for the past 400 to 1100 years to examine similarities of climate oscillation and the resulting cultural changes in North America for the same period. The climatic intervals known as the ‘Medieval Warm Period’,
The author begins with an introduction providing a brief background on Europe during the 700 yr period covered in this study and the organisational framework of the North American data. Each of seven subsequent chapters provides information on a century (starting with the 10th century and ending with the 16th) of climate and cultural changes. Short descriptions of historic European conditions provide a context for describing each century of climate and cultural change in North America. The climate data are drawn predominantly from a report, Surface Temperature Reconstructions for the Last 2,000 Years (National Research Council, 2006), that collated information from diverse sources to identify general temperature trends across North America. Some mention is made of more local or regional climate change studies and, with many reports available on past environments across North America, more examination of local variation could have been included. Although local studies would add more specifics on regional variations of past conditions, this book concentrates on broad comparisons that identify larger trends in the relationship between climate change and past cultural developments over the centuries.
The descriptions of prehistoric cultures are drawn from numerous archaeological reports ranging from site-specific analyses to regional summaries. Foster includes only the southern parts of the USA extending to the extreme northern portion of Mexico in the study. To make comparisons, this area is divided into four sections: the Southwest, the Southern Plains, the Trans-Mississippi South, and the Southeast. This division roughly follows culture areas defined by anthropologists. The northern limits of the study area are defined by the location of major sites and cultures, specifically on the northwest by the Chaco Canyon sites in northern New Mexico, and on the northeast by the Cahokia complex in southwestern Illinois and northeastern Missouri. Descriptions concentrate on prehistoric cultures and major representative sites such as Chaco Canyon, Spiro, Cahokia, or Moundville. The emphasis on significant sites allows for interesting descriptions of past cultures as these sites tend to have been studied more and thus have more information on past subsistence activities, settlement patterns, architecture and artefacts. This emphasis on major sites can, however, also create problems in some comparisons across the four regions. This is evident in Map 1 where the culture areas and major sites are depicted. Most of the Southern Plains area on this map is blank space. In fact, other than a brief mention of Antelope Creek people in the Texas Panhandle region, the author’s use of the Southern Plains is limited to the southern portion of Texas, an area at best on the periphery of the Plains. The main Southern Plains from central Kansas to central Texas is ignored despite the large number of archaeological studies that could be used to fill this void. What this Plains area lacks is the famous site or well-known prehistoric culture that can be easily mined for comparative information.
The descriptions and comparisons of the sites and cultural complexes provide a nice overview of developments in each culture area. Emphasis is placed on economic activities, especially the intensification in cultivation of maize plus other tropical and native plants, and the impact of changing climatic conditions on crop production as well as hunting and gathering activities. Changes in economies are then tied to social and political changes, the rise of monumental architecture and long distance trade, the development of artistic activities, and the intensification of warfare. In the Southwest, for example, the rise of Chaco Canyon in the 10th century as a major centre is tied to the onset of the ‘Medieval Warming Period’ permitting more extensive maize production. Political and ceremonial complexity increases, long-distance trade extends as far as Mesoamerica, astronomical observations are made, and intricate art work is painted on pottery. The sudden decline of Chaco and abandonment of the area in the 13th century is tied to drought and the end of the warm period. Other cultures in southern areas of the Southwest were not affected at the same time reflecting different impacts as the climate became cooler and more mesic. Similar changes are seen in cultures across the Southern Plains and Southeast.
By the 16th century, European explorers were entering the area providing the first historic descriptions of the climate and cultures in the southern USA. From Coronado’s expedition in the Southwest and Plains to De Soto’s expedition in the Southeast and Trans-Mississippi South, the Spanish recorded the impact of much cooler and wetter conditions on native cultures. These historical data add to the archaeological reports indicating a period of consolidation or collapse of some cultures and changes in economies, trade, and technologies during this century.
Foster concludes that ‘… the Medieval Warm Period and the Little Ice Age directly and strongly impacted the climate in North America and substantially influenced the Native culture history …’ (p. 166). While there has long been recognition of the relationship of cultures and environment and the impacts of changing climates on cultures, the significance of Foster’s Climate and Culture Change in North America is the compilation and comparison of information over an extended region and time period. The details of local cultural developments and climate changes in the Southwest, Plains, and Southeast are important, but researchers benefit from studies that place these within broader regional and even national and international patterns of change. This is particularly appropriate for the study period since the economies of agrarian societies that developed in North America at this time were significantly influenced by variations in temperature and moisture that impacted crop production.