February 24, 1863
Arizona becomes a territory
Most of what is now Arizona came into the possession of the US in 1848 after the Mexican-American War. In 1850, it became part of the Territory of New Mexico, which also included the southern parts of Colorado, Nevada, and Utah. More land was added in 1854 when the Gadsden Treaty was signed. In 1858, there was a request for the creation of an Arizona teritory. The Civil War did nothing to help the process as both sides wanted Arizona. Finally, however, Congress approved the creation of the Territory of Arizona and President Abraham Lincoln signed the bill on February 24, 1863.