A breakthrough dendrochronological study of submerged cedar stumps in the Pacific Northwest has pinpointed a "Great Fire" in 900 CE that fundamentally altered Coastal Salish trade. Researchers found that a massive fire-induced collapse of old-growth forests led to a rapid shift in tool production and sedentary patterns among indigenous groups across the region.
The study, published in Archaeological Science, links this environmental catastrophe to a reorganization of maritime trade routes as communities moved to more stable coastal lagoons. The data provides a rare, high-resolution glimpse into how ancient communities responded to sudden and extreme climate-driven landscape changes.