Multiple Hopewellian monumental earthwork sites displaying timber features, mortuary deposits, and unique artifacts are found widely distributed across the North American Eastern Woodlands, from the lower Mississippi Valley north to the Great Lakes. These sites, dating from 200 b.c. to a.d. 500, almost define the Middle Woodland period of the Eastern Woodlands. Joseph Caldwell treated these sites as defining what he termed the Hopewell Interaction Sphere, which he conceptualized as mediating a set of interacting mortuary-funerary cults linking many different local ethnic communities. In...