Awarded Territorial Status 1863 - Statehood 1912

Apache County - formed 1879 County Seat: St. Johns
Cochise County - formed 1881 County Seat: Bisbee
Coconino County - formed 1891 County Seat: Flagstaff
Gila County - formed 1881 County Seat: Globe
Graham County - formed 1881 County Seat: Safford
Greenlee County - formed 1909 County Seat: Clifton
LaPaz County - formed 1983 County Seat: Parker
Maricopa County - formed 1871 County Seat: Phoenix
Mohave County - formed 1864 County Seat: Kingman
Navojo County - formed 1895 County Seat: Holbrook
Pima County - formed 1864 County Seat: Tucson
Pinal County - formed 1875 County Seat: Florence
Santa Cruz County -formed 1899 County Seat: Nogales
Yavapai County - formed 1864 - County Seat: Prescott
Yuma County - formed 1864 - County Seat: Yuma