Arizona: Territory vs. Statehood—Key Dates and the 49-Year Gap

February 24, 1863 – Arizona Territory created from the western half of New Mexico Territory (Gadsden Purchase lands south of the Gila River had been U.S. since 1854).

February 14, 1912 – Arizona admitted as the 48th state.

Gap: 48 years, 11 months, 21 days as a territory before statehood—one of the longest territorial periods in U.S. history.