Traditional Arizona

Prior to the adoption of its name for a U.S. state, Arizona was traditionally defined as the region south of the Gila River to the present-day Mexican border, and between the Colorado River and the Rio Grande. It encompasses present-day Southern Arizona and the New Mexico Bootheel plus adjacent parts of Southwestern New Mexico. This area was transferred from Mexico to the United States in the Gadsden Purchase of 1853. Mining and ranching were the primary occupations of traditional Arizona's inhabitants, though growing citrus fruits had long been occurring in Tucson.

Socio-politically, some of the founders of Arizona were from areas which were once the Republic of Texas, though many were from the area's heartland around Tucson, Arizona, settlers who had flocked to the region during the California Gold Rush of the 1840s. They maintained their eastern links via Mesilla, on traditional Arizona's border with Texas, to San Antonio, Texas. Most others were from elsewhere in the United States of America, as opposed to the Mexican citizens from Sonora and settlers from other settlements of the Midwest. Texas was the lifeline for Arizona, but only until California was established as a U.S. state, meaning Arizona had access to two separate lines of communications and food for frontier settlements. The main line was the Butterfield Overland Mail company, which ran through southern Arizona. Traditional Arizona was never part of William Walker's Republic of Sonora, as it was created in January 1854, a year after the Gadsden Purchase which put traditional Arizona under United States control.

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