Answer
Charles C. Mann portrays the Hopewell Culture as a beacon of civilization in North America.
They were prominent and proficient in the areas of earthworks, agriculture, and societal engineering.
According to him, they ingrained their dominance by religion rather than warfare. Mann portrays the Hopewell Culture was a kingdom of the mind. Because even after the decline of Hopewell, its impacts in and trade and agriculture remained.
See textual evidence below:
"Hopewell itself declined around 400 A.D. But its trade network remained intact."
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