The title the "father of Arizona" is credited to Charles D. Poston.
"Charles Debrille Poston is regarded by historians as the "Father of Arizona." He led the first exploration of what is now Arizona shortly after the Gadsden Purchase in 1853. A few years later, he helped establish the Sonora Mining Company in Tubac, but was forced to flee after the Union pulled its troops out of the area to fight in the Civil War. Poston ultimately went to Washington, where he lobbied congress and President Lincoln to get the Federal Government to officially make Arizona a Territory, with a Territorial Government. When this happened, February 24, 1863, Poston was elected first Territorial Delegate to the U.S. House of Representatives."
Sources:
Paré, Madeline Ferrin. Arizona Pageant: a short history of the 48th State. Phoenix, Arizona Historical Foundation. 1965.
Charles Debrille Poston. Edited by edited by Parker Anderson. History of the Arizona Territory. September 17, 2011 [link no longer available]
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