Arizona Historical Society
Established by an Act of the First Territorial Legislature on November 7, 1864, the Arizona Historical Society (AHS) is Arizona’s oldest historical agency. AHS serves as the steward of state history, fulfilling its mission to collect, preserve, interpret, and disseminate the history of Arizona and the West. Collections, housed in AHS museum facilities throughout the state, number in excess of three million objects.
In Flagstaff, we operate the Pioneer Museum and Riordan Mansion. The Pioneer Museum was built in 1908 to serve as the County Hospital for the Indigent and the County Poor Farm. Riordan Mansion was built in 1904 to house the Riordan Brothers, Tim and Mike, and their families. The brothers owned the Arizona Lumber and Timber Company, a lumber mill in Flagstaff.