NPS

Pleasant Ridge Effigy Mounds Group by Ellison Orr. Surveyed by T.H. Lewis, 1893 & Ellison Orr, 1910. (Marching Bear Group)

Historic Resource Study

Creating A National Monument

On October 25, 1949, President Harry Truman signed a proclamation establishing Effigy Mounds National Monument. The monument consisted of two areas: the Jennings-Liebhardt tract (South Unit) and the Yellow River Unit (North Unit). Sny Magill was not initially included in the monument due to land title problems. This site, however, was federally owned and thereby afforded a degree of protection.

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Administrative History

Just as no one knows why effigy mound building started, no one knows why it ended. Perhaps the more flamboyant Mississippian culture, moving upriver from the south, supplanted the older Woodland lifestyle. The Mississippian culture differed considerably from the Woodland. The Mississippian culture was based on cultivation, primarily of corn, which was supplemented by gathering the resources of stream and forest. There were no significant changes in the tools the Mississippians used save for the addition of bison scapular hoes and a few other agricultural implements.

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