Admitted to the Union on February 14, 1912 as the 48th state. Arizona became a territory in 1863.
- 1860 federal census is extant, covering only Arizona County, which includes only the southern portion of the present-day state.
- 1870 – 1940 federal censuses extant for all counties except for 1890.
| Arkansas | Ashley | Baxter | Benton |
| Boone | Bradley | Calhoun | Carroll |
| Chicot | Clark | Clay | Cleburne |
| Cleveland | Columbia | Conway | Craighead |
| Crawford | Crittenden | Cross | Dallas |
| Desha | Drew | Faulkner | Franklin |
| Fulton | Garland | Grant | Greene |
| Hempstead | Hot Spring | Howard | Independence |
| Izard | Jackson | Jefferson | Johnson |
| Lafayette | Lawrence | Lee | Lincoln |
| Little River | Logan | Lonoke | Madison |
| Marion | Miller | Mississippi | Monroe |
| Montgomery | Nevada | Newton | Ouachita |
| Perry | Phillips | Pike | Poinsett |
| Polk | Pope | Prairie | Pulaski |
| Randolph | St. Francis | Saline | Scott |
| Searcy | Sebastian | Sevier | Sharp |
| Stone | Union | Van Buren | Washington |
| White | Woodruff | Yell |