Pinal County was formed in 1875 from portions of Pima, Maricopa, and Yavapai Counties in Arizona.
Collection includes correspondence, financial accounts, tax lists, and school census reports chiefly related to the Treasurer of Pinal County. Includes assessments of county taxes for the Silver King Mining Company; school census reports for Mammoth, AZ., (1876-1891), and other districts, (1906-1907); as well as tax lists for poll, property, license, delinquent, territorial, and county taxes.