Arizona is a state in the Western , grouped in the Southwestern and occasionally Mountain subregions. Its capital and largest  is Phoenix.

Arizona shares the Four Corners  with Utah to the Colorado to the , and New  to the ; its other neighboring states are  and California to the and the  states of Sonora and Baja  to the and .

Arizona is the 48th and last of the contiguous states to be admitted to the Union, achieving statehood on February 14, 1912.

Historically part of the territory of Alta  in New , it became part of independent in 1821.

After being defeated in the  , ceded much of this territory to the in 1848.

The southernmost portion of the was acquired in 1853 through the Gadsden Purchase.

Southern Arizona is known for its desert climate, with very hot summers and mild winters.

Northern Arizona features forests of pine, Douglas fir, and spruce trees; the  Plateau; mountain ranges; as well as large, deep canyons, with much more moderate summer temperatures and significant winter snowfalls.

There are  resorts in the areas of Flagstaff, Alpine, and Tucson.

In addition to the internationally known Grand Canyon National Park, which is one of the world’s seven natural wonders, there are several national forests, national parks, and national monuments.

Since the 1950s, Arizona’s population and economy have grown dramatically because of migration into the , and now the is a major hub of the Sun Belt.

Cities such as Phoenix and Tucson have developed large, sprawling suburban areas.

Many large companies, such as PetSmart and Circle K, have headquarters in the , and Arizona is home to major universities, including the University of Arizona and Arizona University.

Traditionally, the is politically known for national conservative figures such as Barry Goldwater and John McCain, though it voted Democratic in the 1996 presidential race and in the 2020 presidential and senatorial elections.

About one-quarter of the  is made up of Indian reservations that serve as the home of 27 federally recognized tribes, including the Navajo Nation, the largest in the and the , with more than 300,000 citizens.

Since the 1980s, the proportion of Hispanics in the ’s population has grown significantly owing to migration from .

The also has a substantial Catholic and Mormon population.