In 1539, Marcos de Niza, a Spanish Franciscan, became the first European to contact Native Americans. He explored parts of the present state and made contact with native inhabitants, probably the Sobaipuri. The expedition of Spanish explorer Coronado entered the area in 1540–1542 during its search for Cíbola. Few Spanish settlers migrated to Arizona. One of the first settlers in Arizona was José Romo de Vivar.
Father Kino was the next European in the region. A member of the Society of Jesus ("Jesuits"), he led the development of a chain of missions in the region. He converted many of the Indians to Christianity in the Pimería Alta (now southern Arizona and northern Sonora) in the 1690s and early 18th century. Spain founded presidios ("fortified towns") at Tubac in 1752 and Tucson in 1775.
Arizona is the 48th state 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 California in New Spain, it became part of independent Mexico in 1821. After being defeated in the Mexican–American War, Mexico ceded much of this territory to the United States in 1848. The southernmost portion of the state was acquired in 1853 through the Gadsden Purchase.
When Mexico achieved its independence from the Kingdom of Spain and its Spanish Empire in 1821, what is now Arizona became part of its Territory of Nueva California, ("New California"), also known as Alta California ("Upper California"). Descendants of ethnic Spanish and mestizo settlers from the colonial years still lived in the area at the time of the arrival of later European-American migrants from the United States.
During the Mexican–American War (1847–1848), the U.S. Army occupied the national capital of Mexico City and pursued its claim to much of northern Mexico, including what later became Arizona Territory in 1863 and later the State of Arizona in 1912. The Treaty of Guadalupe Hidalgo (1848) specified that, in addition to language and cultural rights of the existing inhabitants of former Mexican citizens being considered as inviolable, the sum of $15 million in compensation (equivalent to $443,250,000 in 2019.) be paid to the Republic of Mexico. In 1853, the U.S. acquired the land south below the Gila River from Mexico in the Gadsden Purchase along the southern border area as encompassing the best future southern route for a transcontinental railway.
What is now known as the state of Arizona was initially administered by the United States government as part of the Territory of New Mexico until the southern part of that region seceded from the Union to form the Territory of Arizona. This newly established territory was formally organized by the Confederate States government on Saturday, January 18, 1862, when President Jefferson Davis approved and signed An Act to Organize the Territory of Arizona, marking the first official use of the name "Territory of Arizona". The Southern territory supplied the Confederate government with men, horses, and equipment. Formed in 1862, Arizona scout companies served with the Confederate States Army during the Civil War. Arizona has the westernmost military engagement on record during the Civil War with the Battle of Picacho Pass.
The Federal government declared a new U.S. Arizona Territory, consisting of the western half of earlier New Mexico Territory, in Washington, D.C., on February 24, 1863. These new boundaries would later form the basis of the state. The first territorial capital, Prescott, was founded in 1864 following a gold rush to central Arizona. The capital was later moved to Tucson, back to Prescott, and then to its final location in Phoenix in a series of controversial moves as different regions of the territory gained and lost political influence with the growth and development of the territory.
Tucson, with a metro population of just over one million, is the state's second-largest city. Located in Pima County, approximately 110 miles (180 km) southeast of Phoenix, it was incorporated in 1877, making it the oldest incorporated city in Arizona. It is home to the University of Arizona. Major incorporated suburbs of Tucson include Oro Valley and Marana northwest of the city, Sahuarita south of the city, and South Tucson in an enclave south of downtown. It has an average July temperature of 100 °F (38 °C) and winter temperatures averaging 65 °F (18 °C). Saguaro National Park, just west of the city in the Tucson Mountains, is the site of the world's largest collection of Saguaro cacti.
College sports are also prevalent in Arizona. The Arizona State Sun Devils and the Arizona Wildcats belong to the Pac-12 Conference while the Northern Arizona Lumberjacks compete in the Big Sky Conference and the Grand Canyon Antelopes compete in the Western Athletic Conference. The rivalry between Arizona State Sun Devils and the Arizona Wildcats predates Arizona's statehood, and is the oldest rivalry in the NCAA. The Territorial Cup, first awarded in 1889 and certified as the oldest trophy in college football, is awarded to the winner of the annual football game between the two schools.
The state capital of Arizona is Phoenix. The original Capitol building, with its distinctive copper dome, was dedicated in 1901 (construction was completed for $136,000 in 1900), when the area was a territory. Phoenix became the official state capital with Arizona's admission to the union in 1912.
The earliest Arizona earthquakes were recorded at Fort Yuma, on the California side of the Colorado River. They were centered near the Imperial Valley, or Mexico, back in the 1800s. Residents in Douglas felt the 1887 Sonora earthquake with its epicenter 40 miles (64 km) to the south in the Mexican state of Sonora. The first damaging earthquake known to be centered within Arizona occurred on January 25, 1906, also including a series of other earthquakes centered near Socorro, New Mexico. The shock was violent in Flagstaff.
Arizona's population grew tremendously with residential and business development after World War II, aided by the widespread use of air conditioning, which made the intensely hot summers more comfortable. According to the Arizona Blue Book (published by the Arizona Secretary of State's office each year), the state population in 1910 was 294,353. By 1970, it was 1,752,122. The percentage growth each decade averaged about 20% in the earlier decades, and about 60% each decade thereafter.
In September 1910, a series of 52 earthquakes caused a construction crew near Flagstaff to leave the area. In 1912, the year Arizona achieved statehood, on August 18, an earthquake caused a 50-mile crack in the San Francisco Range. In early January 1935, the state experienced a series of earthquakes, in the Yuma area and near the Grand Canyon. Arizona experienced its largest earthquake in 1959, with a tremor of a magnitude 5.6. It was centered near Fredonia, in the state's northwest near the border with Utah. The tremor was felt across the border in Nevada and Utah.
Arizona became a U.S. state on February 14, 1912. Arizona was the 48th state admitted to the U.S. and the last of the contiguous states to be admitted.
During the Mexican Revolution from 1910 to 1920, several battles were fought in the Mexican towns just across the border from Arizona settlements. Throughout the revolution, many Arizonans enlisted in one of the several armies fighting in Mexico. Only two significant engagements took place on U.S. soil between U.S. and Mexican forces: Pancho Villa's 1916 Columbus Raid in New Mexico, and the Battle of Ambos Nogales in 1918 in Arizona. The Americans won the latter.
About one-quarter of the state is made up of Indian reservations that serve as the home of 27 federally recognized Native American tribes, including the Navajo Nation, the largest in the state and the United States, with more than 300,000 citizens. Although federal law gave all Native Americans the right to vote in 1924, Arizona excluded those living on reservations in the state from voting until the state Supreme Court ruled in favor of Native American plaintiffs in Trujillo v. Garley (1948).
In 1924, Congress had passed a law granting citizenship and suffrage to all Native Americans, some of whom had previously been excluded as members of tribes on reservations. Legal interpretations of Arizona's constitution prohibited Native Americans living on reservations from voting, classifying them as being under "guardianship". This interpretation was overturned as being incorrect and unconstitutional in 1948 by the Arizona Supreme Court, following a suit by World War II Indian veterans Frank Harrison and Harry Austin, both of the Fort McDowell Yavapai Nation. The landmark case is Harrison and Austin v. Laveen. After the men were refused the opportunity to register in Maricopa County, they filed suit against the registrar. The National Congress of American Indians, the Department of Justice, the Department of the Interior, and the American Civil Liberties Union all filed amicus curiae (friends of the court) briefs in the case. The State Supreme Court established the rights of Native Americans to vote in the state; at the time, they comprised about 11% of the population. That year, a similar provision was overturned in New Mexico when challenged by another Indian veteran in court. These were the only two states that had continued to prohibit Native Americans from voting.
Arizona was the site of German prisoner of war camps during World War II and Japanese American internment camps. Because of wartime fears of a Japanese invasion of the U.S. West Coast (which in fact materialized in the Aleutian Islands Campaign in June 1942), the government authorized the removal of all Japanese American residents from all the Alaska Territory and California, the western halves of Washington and Oregon, and Southern Arizona. From 1942 to 1945, they were forced to reside in internment camps built in the interior of the country. Many lost their homes and businesses. The camps were abolished after World War II.
Arizona is a popular location for Major League Baseball spring training, as it is the site of the Cactus League. Spring training was first started in Arizona in 1947, when Brewers owner Veeck sold them in 1945 but went onto purchase the Cleveland Indians in 1946. He decided to train the Cleveland Indians in Tucson and convinced the New York Giants to give Phoenix a try. Thus the Cactus League was born.
Numerous Native Americans from Arizona fought for the United States during World War II. Their experiences resulted in a rising activism in the postwar years to achieve better treatment and civil rights after their return to the state. After Maricopa County did not allow them to register to vote, in 1948 veteran Frank Harrison and Harry Austin, of the Mojave-Apache Tribe at Fort McDowell Indian Reservation, brought a legal suit, Harrison and Austin v. Laveen, to challenge this exclusion. The Arizona Supreme Court ruled in their favor.
Since the election of Dwight D. Eisenhower in 1952, the majority of state voters have favored Republicans in presidential elections. Arizona voted Republican in every presidential election from 1952 to 1992, with Richard Nixon and Ronald Reagan winning the state by particularly large margins. During this forty-year span, it was the only state not to be carried by a Democrat at least once.
In the 1960s, retirement communities were developed. These age-restricted subdivisions catered exclusively to the needs of senior citizens and attracted many retirees who wanted to escape the harsh winters of the Midwest and the Northeast. Sun City, established by developer Del Webb and opened in 1960, was one of the first such communities. Green Valley, south of Tucson, was another such community, designed as a retirement subdivision for Arizona's teachers. Many senior citizens from across the U.S. and Canada come to Arizona each winter and stay only during the winter months; they are referred to as snowbirds.
The House of Representatives and Senate buildings were dedicated in 1960, and an Executive Office Building was dedicated in 1974 (the ninth floor of this building is where the Office of the Governor is located). The original Capitol building was converted into a museum.
Lake Havasu City, in Mohave County, known as "Arizona's playground", was developed on the Colorado River and is named after Lake Havasu. Lake Havasu City has a population of about 53,000 people. It is famous for huge spring break parties, sunsets and the London Bridge, relocated from London, England. Lake Havasu City was founded by real estate developer Robert P. McCulloch in 1963. It has two colleges, Mohave Community College and ASU Colleges in Lake Havasu City.
Democrat Lyndon Johnson, in 1964, lost the state by less than 5,000 votes to Arizona Senator and native Barry Goldwater. (This was the most closely contested state in what was otherwise a landslide victory for Johnson that year.) Democrat Bill Clinton ended this streak in 1996, when he won Arizona by a little over two percentage points (Clinton had previously come within less than two percent of winning Arizona's electoral votes in 1992). Since then, the majority of the state has continued to support Republican presidential candidates by solid margins.
On March 4, 2008, Senator John McCain effectively clinched the Republican nomination for 2008, becoming the first presidential nominee from the state since Barry Goldwater in 1964.
About midway through February, the temperatures start to rise, with warm days, and cool, breezy nights. The summer months of June through September bring a dry heat from 90 to 120 °F (32 to 49 °C), with occasional high temperatures exceeding 125 °F (52 °C) having been observed in the desert area. Arizona's all-time record high is 128 °F (53 °C) recorded at Lake Havasu City on June 29, 1994, and July 5, 2007; the all-time record low of −40 °F (−40 °C) was recorded at Hawley Lake on January 7, 1971.
"Arizona" was the title of a popular song recorded by Mark Lindsay. Arizona is mentioned by the hit song "Take It Easy", written by Jackson Browne and Glenn Frey and performed by the Eagles. Arizona is also mentioned in the Beatles' song "Get Back", credited to John Lennon and Paul McCartney; McCartney sings: "JoJo left his home in Tucson, Arizona, for some California grass." "Carefree Highway", released in 1974 by Gordon Lightfoot, takes its name from Arizona State Route 74 north of Phoenix.
In 1980, the Census Bureau reported Arizona's population as 16.2% Hispanic, 5.6% Native American, and 74.5% non-Hispanic white. In 2010, the racial makeup of the state was:
Arizona is also known for its heavy metal scene, which is centered in and around Phoenix. In the early to mid-1990s, it included bands such as Job for a Cowboy, Knights of the Abyss, Greeley Estates, Eyes Set To Kill, blessthefall, The Word Alive, The Dead Rabbitts, and Abigail Williams. The band Soulfly calls Phoenix home and Megadeth lived in Phoenix for about a decade. Beginning in and around 2009, Phoenix began to host a burgeoning desert rock and sludge metal underground, (ala' Kyuss in 1990s California) led by bands like Wolves of Winter, Asimov, and Dead Canyon.
On March 9, 1995, Arizona was awarded a franchise to begin to play for the 1998 season. A $130 million franchise fee was paid to Major League Baseball and on January 16, 1997, the Diamondbacks were officially voted into the National League.
Amtrak Southwest Chief route serves the northern part of the state, stopping at Winslow, Flagstaff, Williams and Kingman. The Texas Eagle and Sunset Limited routes serve South-Central Arizona, stopping at Tucson, Maricopa, Yuma and Benson. Phoenix lost Amtrak service in 1996 with the discontinuation of the Desert Wind, and now an Amtrak bus runs between Phoenix and the station in Maricopa.
In March 2000, Arizona was the site of the first legally binding election ever held over the internet to nominate a candidate for public office. In the 2000 Arizona Democratic Primary, under worldwide attention, Al Gore defeated Bill Bradley. Voter turnout in this state primary increased more than 500% over the 1996 primary.
Arizona has a wide network of two-year vocational schools and community colleges. These colleges were governed historically by a separate statewide board of directors but, in 2002, the state legislature transferred almost all oversight authority to individual community college districts. The Maricopa County Community College District includes 11 community colleges throughout Maricopa County and is one of the largest in the nation.
The Mogollon Rim, a 1,998-foot (609 m) escarpment, cuts across the state's central section and marks the southwestern edge of the Colorado Plateau. In 2002, this was an area of the Rodeo–Chediski Fire, the worst fire in state history.
Arizona is home to the largest number of speakers of Native American languages in the 48 contiguous states, as more than 85,000 individuals reported speaking Navajo, and 10,403 people reported Apache, as a language spoken at home in 2005. Arizona's Apache County has the highest concentration of speakers of Native American Indian languages in the United States.
Public schools in Arizona are separated into about 220 local school districts which operate independently, but are governed in most cases by elected county school superintendents; these are in turn overseen by the Arizona State Board of Education (a division of the Arizona Department of Education) and the state Superintendent of Public Instruction (elected in partisan elections every even-numbered year when there is not a presidential election, for a four-year term). In 2005, a School District Redistricting Commission was established with the goal of combining and consolidating many of these districts.
In 2006, Arizona became the first state in the United States to reject a proposition, Prop 107, that would have banned same-sex marriage and civil unions. However, in 2008, Arizona voters approved of Prop 102, a constitutional amendment that prohibited same-sex marriage but not other unions. Prior to same-sex marriage being legal, the City of Bisbee became the first jurisdiction in Arizona to approve of civil unions. The state's Attorney General at the time, Tom Horne, threatened to sue, but rescinded the threat once Bisbee amended the ordinance; Bisbee approved of civil unions in 2013. The municipalities of Clarkdale, Cottonwood, Jerome, Sedona, and Tucson also passed civil unions.
The fiscal year 2006–07 general fund budget, approved by the Arizona Legislature in June 2006, is slightly less than $10 billion. Besides the money spent on state agencies, it also includes more than $500 million in income and property tax cuts, pay raises for government employees, and additional funding for the K–12 education system.
Arizona rejected a same-sex marriage ban in a referendum as part of the 2006 elections. Arizona was the first state in the nation to do so. Same-sex marriage was not recognized in Arizona, but this amendment would have denied any legal or financial benefits to unmarried homosexual or heterosexual couples. In 2008, Arizona voters passed Proposition 102, an amendment to the state constitution to define marriage as a union of one man and one woman. It passed by a more narrow majority than similar votes in a number of other states.
Maricopa County is home to almost 60 percent of the state's population, and most of the state's elected officials live there. It has voted Republican in every presidential election since 1948. This includes the 1964 run of native son Barry Goldwater; he would not have carried his home state without his 20,000-vote margin in Maricopa County. Similarly, while McCain won Arizona by eight percentage points in 2008, aided by his 130,000-vote margin in Maricopa County.
State Farm Stadium hosted Super Bowl XLII on February 3, 2008, and Super Bowl XLIX on February 1, 2015. The stadium is also scheduled to host Super Bowl LVII tentatively scheduled for February 5, 2023.
A November 2011 Public Policy Polling survey found 44% of Arizona voters supported the legalization of same-sex marriage, while 45% opposed it and 12% were not sure. A separate question on the same survey found 72% of respondents supported legal recognition of same-sex couples, with 40% supporting same-sex marriage, 32% supporting civil unions, 27% opposing all legal recognition and 1% not sure. Arizona Proposition 102, known by its supporters as the Marriage Protection Amendment, appeared as a legislatively referred constitutional amendment on the November 4, 2008 ballot in Arizona, where it was approved: 56.2%–43%. It amended the Arizona Constitution to define marriage as between one man and one woman.
A light rail system, called Valley Metro Rail, was completed in December 2008; it connects Central Phoenix with the nearby cities of Mesa and Tempe.
According to the 2010 United States Census, Arizona had a population of 6,392,017. In 2010, illegal immigrants constituted an estimated 7.9% of the population. This was the second highest percentage of any state in the U.S. Arizona has banned sanctuary cities.
According to the Association of Religion Data Archives, the fifteen largest denominations by number of adherents in 2010 and 2000 were:
Hinduism became the largest non-Christian religion (when combining all denominations) in 2010 with more than 32,000 adherents, followed by Judaism with more than 20,000 and Buddhism with more than 19,000.
In 2010, Arizona passed SB 1070, called the toughest illegal immigration legislation in the nation. A fierce debate erupted between supporters and detractors of the law.
In 2010, the Association of Religion Data Archives reported that the three largest denominational groups in Arizona were the Catholic Church, The Church of Jesus Christ of Latter-Day Saints and non-denominational Evangelical Protestants. The Catholic Church has the highest number of adherents in Arizona (at 930,001), followed by The Church of Jesus Christ of Latter-day Saints with 410,263 members reported and then non-denominational Evangelical Protestants, reporting 281,105 adherents. The religious body with the largest number of congregations is The Church of Jesus Christ of Latter-day Saints (with 836 congregations) followed by the Southern Baptist Convention (with 323 congregations).
The United States Supreme Court heard arguments March 18, 2013, regarding the validity of the Arizona law, which requires individuals to show documents proving U.S. citizenship in order to register to vote in national elections.
In Tucson, the Sun Link streetcar system travels through the downtown area, connecting the main University of Arizona campus with Mercado San Agustin on the western edge of downtown Tucson. Sun Link, loosely based on the Portland Streetcar, launched in July 2014.
The top employment sectors in Arizona are (August 2014, excludes agriculture):
On October 17, 2014, Arizona Attorney General Tom Horne announced his office would no longer object to same-sex marriage, in response to a U.S. District Court Ruling on Arizona Proposition 102. On that day, each county's Clerk of the Superior Court began to issue same-sex marriage licenses, and Arizona became the 31st state to legalize same-sex marriage.
The state government is Arizona's largest employer, while Banner Health is the state's largest private employer, with more than 39,000 employees (2016). As of March 2016 , the state's unemployment rate was 5.4%.
State Farm Stadium hosted the Final Four of the NCAA Division I Men's Basketball Tournament in 2017 and is scheduled to host it again in 2024.
The West Virginia teachers' strike in 2018 inspired teachers in other states, including Arizona, to take similar action.
Arizona's two United States Senators are Kyrsten Sinema (D) and Martha McSally (R). McSally, after losing to Sinema was appointed by Governor Ducey to succeed acting senator Jon Kyl to fill the spot formerly occupied by the late six-term senior Senator John McCain, who died August 25, 2018. Senator McSally, will serve in office until a special election in 2020.
The United States Census Bureau estimates Arizona's population was 7,278,717 on July 1, 2019, a 13.87% increase since the 2010 United States Census.