SOME CORRELATIONS OF CLIMATIC AND CULTURAL CHANGE IN EASTERN NORTH AMERICAN PREHISTORY

Abstract

There is thus far relatively little direct evidence for climatic change from archaeological sites in the eastern United States. Archaeologists have considered for many years that the dividing line between eastern and western is the eastern side of the Rocky Mountains. This whole area then, has become a convenient unit of prehistoric studies because of the obvious connections and similarities at all known time periods and all of the cultural levels. Since A. D. Krieger, in his paper in this volume, emphasizes the initial occupation in North America, my attention will be primarily devoted to the last 4000 to 5000 years. Before one can interpret cultural changes as resulting from climatic variation it is highly desirable to have one’s prehistoric house in reasonable order. Sound chronological and stratigraphic sequences need to be developed over a wide area, and cultural complexes need to be carefully defined in local areas and in their correct and reasonably precise temporal position in order to observe the effects of climatic change on cultural behavior. Not only is a sound and laboriously obtained archaeological framework necessary, but there needs to be a sound corpus of data regarding floral and faunal changes, of soil zones, and of other climatic indicators in general ecological areas or zones. The pollen studies of the past 30 years have been a great help, and radiocarbon dating is providing an increasingly accurate chronological scale. Three years ago, while working on a paper on the prehistory of the Winnebago tribe of Wisconsin (Griffin, 19606), I developed the thesis that the observed cultural decline in the Upper Mississippi Valley of the Winnebago and their ancestors could be explained, at least to some degree, as the result of a climatic deterioration that corresponded to that accurately documented in Northern Europe and Greenland from about A.D. 1200 to 1700. Beginning a few hundred years before A.D. 1000 there developed in the East St. Louis area an agricultural, sedentary culture type that is a regioiial expression of an increasing emphasis on agriculture known in much of the eastern area as the Mississippi culture (Griffin, 1952). The Old Village complex of Mississippi culture in the St. Louis area exerted a strong influence to the north and northwest, up the Illinois, Mississippi, and the Missouri valleys. I t is certain that there was a strong movement of people into southern and western Wisconsin by about A.D. 700 to 800 (M-1037) and into eastern Minnesota, taking with them their customary cultural characteristics and their predominantly agricultural economy. Somewhat similar but apparently less strong influences moved into northwest Iowa and ioutheastern South Dakota. From the archaeological evidence, we had known for some time that the late prehistoric and early historic culture of the Upper Mississippi area, called Oneota, was a descendant of the Old Village tradition (Griffin, 1943, p. 302) that had shifted away from a marked dependence on agriculture to a heavier