[3] With a new railroad being built and change on its way to Tucson, Arizona, pioneers worried that their stories of battles with the desert heat and the Apaches would be lost forever.

[2] Over time, the Society evolved to provide storage for official state papers and collect the histories of many Arizona citizens.

Collections expanded beyond the capacity of facilities several times, until a large, block-long basement was created to store records and documents at the current Main Museum.

Tempe Collections Strengths: 20th Century, Maricopa County and Central Arizona, oral histories, architectural drawings, TV news reels, aviation, banking, healthcare, business, non-profit organizations, arts and culture, photographs and photographic studios.

Flagstaff Collections Strengths: Territorial era to 1950s, Northern Arizona and Colorado Plateau, business, politics, law, lumber industry, railroads, genealogy, local organizations, Indian Pow Wow records, education, healthcare, maps, oral histories and photographs.