Smithsonian archaeologist Cyrus Thomas demonstrated in the 1890s that the effigy, burial, and temple mounds of the Northeast and Southeast United States were built by Native Americans, not by a separate 'Mound Builder' civilization.
Notes on verification
Confirmed by Britannica's biography of Cyrus Thomas, EBSCO, American Heritage, and Lapham's Quarterly, all independently corroborating the claim's details on timeframe, Smithsonian affiliation, mound types, and regions. [tier=unverified indep_score=0.3 clusters=3 claim_tier=notable] [rescored 2026-09-15: curated origin-host map (PR #65); unclassified hosts no longer scored as aggregators]
Sources
- Native American - Prehistory, Tribes, Culture | Britannica (seed:history_and_archaeology)
- https://www.ebsco.com/research-starters/anthropology/mounds-and-mound-builders (corroboration)
- https://www.americanheritage.com/mound-country (corroboration)
- https://www.laphamsquarterly.org/contributors/cyrus-thomas (corroboration)