Founded in 1934 in Stillwater, Minnesota, the Washington County Historical Society grew from earlier local efforts to preserve memories of the St. Croix Valley and Washington County. Beginning with documents, photographs, and family histories gathered at the Stillwater Public Library, it expanded into stewardship of major historic sites, including the Warden’s House Museum, Hay Lake School, the Johannes Erickson Log Home, and Boutwell Cemetery. Its work broadened further with improved archival storage and, in 2021, the opening of the Washington County Heritage Center. Through exhibits, archives, preserved buildings, and educational programs, it serves as a central keeper of the county’s history and everyday life.