Interpersonal violence (warfare or domestic squabble?) - Cahokia point embedded in human sacrum.

Perino, G. H. 1971. The Mississippian Components at the Schild site (No. 4) Greene County, Illinois. In Mississippian Site Archaeology in Illinois: I. Site Reports from the St. Louis and Chicago Areas, edited by J.A. Brown, pp. 1-148. IAS Bulletin No. 8. Fig. 23, p.58

Image courtesy of Illinois Archaeological Survey.