The first Native Americans arrived in Arizona between 16,000 BC and 10,000 BC, while the history of Arizona as recorded by Europeans began when Marcos de Niza, a Franciscan, explored the area in 1539. Coronado's expedition entered the area in 1540–1542 during its search for Cíbola. Padre Eusebio Francisco Kino developed a chain of missions and taught the Indians Christianity in Pimería Alta (now southern Arizona and northern Sonora) in the 1690s and early 18th century. Spain founded fortified towns (presidios) at Tubac in 1752 and Tucson in 1775.
All of present-day Arizona became part of the Mexican State of Vieja California upon the Mexican assertion of independence from Spain in 1822. The United States took possession of most of Arizona at the end of the Mexican-American War in 1848. In 1853, the land below the Gila River was acquired from Mexico in the Gadsden Purchase. Arizona was administered as part of the Territory of New Mexico until it was organized into a separate territory on February 24, 1863.
Arizona was admitted into the Union—officially becoming a U.S. state—on February 14, 1912.
According to the best archaeological and geological evidence available, Paleolithic, mammoth-hunting families moved into northwestern North America sometime between 16,000 BC and 10,000 BC. In central Alaska, they found their passage blocked by a huge sheet of ice until a temporary recession in the last ice age that opened up an ice-free corridor through northwestern Canada, allowing bands to fan out throughout the rest of the continent. The earliest undisputed evidence of humans in the southwestern United States is a set of fluted spear points from the Paleolithic. Some scientists have proposed that small bands of women, men and children wandered across the deserts of southwestern Arizona en refuge in present-day Mexico.
Temperatures rose, and the seasonal distribution of precipitation began to change, causing major changes in the vegetation as well. The Clovis people were stalking mammoths and other ice-age species in southeastern Arizona at a time when many streams were drying up, forcing animals to concentrate around streams and seeps. The growing aridity of the region therefore coincided with the arrival of hunters who specialized in the pursuit of large mammals. It is possible that climate and humans acted together to bring an end to these species.
Arizona grew even more arid after the last ice age came to an end. Summers grew wetter, but warmer, so rainfall evaporated quicker. Winters became considerably drier, making less moisture available to plants. In southern Arizona, woodlands gave way to desert grasslands, and desert grasslands gave way to desert scrub. Important Sonoran Desert species like saguaro and brittlebush began to recolonize the region from the south, while ponderosa forests and piñon-juniper-oak woodlands climbed back onto the Colorado Plateau. By 2000 BC, the modern plant communities of Arizona had been established and a modern climate prevailed.
The early Archaic peoples of Arizona survived these changes by adapting to the cycles of plants rather than trying to change them. In the woodlands, they gathered acorns in July and August, and piñon nuts and juniper berries in November. In the desert, they picked the leaves of annual plants like chenopodium (goosefoot) and amaranth (pigweed). They also roasted agave in rock-lined pits each spring, and collected cactus fruit and harvested mesquite pods in the summer. Because of their dependence on scattered and seasonal resources, Archaic groups did not occupy permanent settlements. Instead, they wandered from camp to camp in search of water and wild foods.
Their tools reflected their economy: ground stones (manos and metates) were used for grinding seeds into flour, scrapers for working hide and wood, and projectile points, smaller and cruder than the earlier Clovis and Folsom points, for hunting large and small game. The varying proportions of such tools at different sites suggest that people moved back and forth between different environmental zones to exploit their particular resources. Archaic peoples fashioned artifacts that demonstrated their capacity for wonder and their quest for supernatural power. Intaglios (sand drawings) 10 to 100 feet (30 m) in length appeared on both sides of the Colorado River in southeastern California and southwestern Arizona. Many of them were of stylized rattlesnakes, thunderbirds, phalli, and human forms.
The introduction of agriculture
For most of the Archaic period, people were not able to transform their natural environment in any fundamental way. Many archaeologists assumed that the Archaic cultures of Arizona were dead ends. They believed groups outside the region, particularly Mesoamerica, introduced major innovations like agriculture into the Southwest. According to this model, maize first put down Southwestern roots in the highlands of western New Mexico and eastern Arizona, the pre-Hispanic cultural area known as the Mogollon. Archaic populations there began growing a small and primitive variety of maize at places like Bat Cave as early as 3500 BCE. From there, maize spread slowly to more arid and lowland areas, such as the Sonoran Desert.
During the 1980s, these early maize dates were challenged by a refinement in radiocarbon dating using the accelerator mass spectrometer (AMS) technique. Accelerator dates reveal that the first corn from Bat Cave and other highland sites appeared around 1000 BCE, 2,500 years later than previously thought. A number of sites excavated in southern Arizona demonstrate that Archaic farmers were cultivating maize in the Tucson Basin at around the same time as well. At the Milagro site along Tanque Verde Creek, for example, a Late Archaic population built pit houses, dug bell-shaped storage pits, and planted maize around 850 BCE. Archaic groups, then, were already beginning to make the transition from food gatherers to food producers around 3,000 years ago. They also possessed many of the cultural features that accompany semisedentary agricultural life: storage facilities, more permanent dwellings, larger settlements, and even cemeteries.
Despite the early advent of farming, late Archaic groups still exercised little control over their natural environment. Furthermore, wild food resources remained important components of their diet even after the invention of pottery and the development of irrigation. The introduction of agriculture never resulted in the complete abandonment of hunting and foraging, even in the largest of Archaic societies. During the 1st millennium CE, at least three major cultures flourished in the Southwest: the Anasazi, the Hohokam, and the Mogollon. These three cultures are well known for their architecture and pottery. In the early 2nd millennium CE the Sinagua and Salado culture rapidly rose to prominence, yet after several hundred years they just as quickly disappeared.
European/North American colonization
Although the first European visitors to Arizona may have come in 1528, the most influential expeditions in early Spanish Arizona were those of Marcos de Niza and Francisco Vásquez de Coronado. The accounts of the early Spanish explorers of large mythical cities like Cíbola and large mineral deposits of copper and silver would attract settlers and miners to the region in later years. These explorations led to the Columbian Exchange in Arizona, and widespread epidemics of smallpox among the Native Americans. Native-American history of early European Arizonan exploration is hard to find, but the O'odham calendar stick is a traditional way of recording notable events, including droughts, invasions, floods that could be used as a source.
Early Franciscans and Jesuits in Arizona also set up numerous missions around the area to convert the Native Americans, such as San Xavier del Bac. The missionary Eusebio Kino developed a chain of missions around the Pimería Alta, exchanging gifts and catechizing the natives, who were then used as scouts for keeping track of events on the frontier. In 1680, the Pueblo Revolt drove Spaniards temporarily from northern New Mexico, but the area was reconquered in 1694.
Although the Spanish did not yet have towns for themselves, in the late 17th century, colonists began steadily entering the region, attracted by the recent discovery of deposits of silver (see Silver mining in Arizona) around the Arizonac mining camp. Most of the colonists left after Juan Bautista de Anza announced it had merely been buried treasure; however, several stayed and became subsistence farmers. During the mid-18th century, the pioneers of Arizona tried to expand their territory northward, but were prevented from doing so by the Tohono O'odham and Apache Native Americans, who had begun raiding their villages for livestock.
In 1765, the Bourbon Reforms began, with Charles III of Spain doing a major rearranging of the presidios (military fortresses) on the northern frontier. The Jesuits were expelled from the area, and the Franciscans took their place at their missions. In the 1780s and 1790s, the Spanish began a plan of setting up Apache peace camps and providing the Apache with rations so that they would not attack, allowing the Spanish to expand northward.
For the most part, Spanish Arizona had a subsistence economy, with occasional small gold and silver mining operations.
In 1821, Mexico won its independence from Spain after a decade of war. The revolution had destroyed the colonial silver mining industry and had bankrupted the national treasury. Along the northern frontier, funds that had supported missions, presidios and Apache peace camps nearly disappeared. As a result, Apaches once again began raiding, running off horse herds, and killing anyone caught outside presidial walls. As missions began to wither, Mexico began auctioning off more land, causing the Pimería Alta and the Apachería to shrink as territory expanded. In the meantime, American mountain men began to enter the region, looking to trap beavers for their pelts.
In 1836, Texas declared independence from Mexico and claimed much of the territory in the northern lands of Mexico. When the United States annexed Texas in 1846 over the strong objections of the Mexican government, U.S. troops moved into disputed territory. Despite offers to buy the disputed lands from Mexico, hostilities erupted in what is known as the Mexican-American War (1846–1848). The U.S. occupied Mexico City and forced the newly founded Mexican Republic to give up its northern half, including the later Arizona.
In the Treaty of Guadalupe Hidalgo (1848), Mexico ceded to the U.S., together with many more territories, approximately the northern 70% of what is today Arizona, while this treaty also specified that the U.S. pay Mexico the sum of US $15 million in compensation. In 1849, the California Gold Rush led as many as 50,000 miners through the region, leading to major booms in Arizona's population. In 1850, the aforementioned 70% of Arizona, together with most of present day New Mexico, was organized as the New Mexico Territory. In 1853, President Franklin Pierce sent James Gadsden to Mexico City to negotiate with Santa Anna, and the United States bought the remaining area of Arizona and New Mexico in the Gadsden Purchase.
Starting in 1853, the entirety of present-day Arizona was part of the New Mexico Territory. During the Civil War, on March 16, 1861, southern New Mexico Territory around Mesilla (now in New Mexico) and Tucson declared itself independent from the United States to join the Confederacy. Confederate Territory of Arizona (CSA) was regarded as a valuable route for possible access to the Pacific Ocean, with the specific intention of joining southern California to the Confederacy. [In 1860, Southern California had cleared all legal hurdles for secession from the rest of California and was waiting reorganization as a new U.S. territory, which never materialized. At that time, sparsely populated Southern California was a hotbed of Southern sympathizers.]
In March 1862, Union troops re-captured the Confederate Territory of Arizona and returned it to the New Mexico Territory.
The Battle of Picacho Pass, April 15, 1862, was a battle of the Civil War fought in the CSA and one of many battles to occur in Arizona during the war. Between three sides, Apaches, Confederates and Union forces. In 1863, the U.S. split up their New Mexico Territory along a north-south border to create the U.S. Arizona Territory, which was later to become the state of Arizona.
During the war, U.S. presidios were moved to New Mexico, leaving Arizona vulnerable to Native American attack. Hostilities between the Native Americans and American settlers began in 1861, lasted until 1886, and led to most Indian tribes being moved to reservations.
Mining, cattle and railroads became the central parts of the Arizona economy, leading to boomtowns being formed as prospectors found gold, and the boomtowns' becoming ghost towns as the miners left. Hispanics, the majority of the population, constituted most of the mining labor force.
The Desert Land Act of 1877, which gave settlers 640 acres (1 sq. mi., 2.6 km²) of land, caused people to flood into the region.
In the 20th century, Arizona almost entered the Union as part of New Mexico in a Republican plan to keep control of the U.S. Senate. The plan, while accepted by most in New Mexico, was rejected by most Arizonans. Progressives in Arizona favored inclusion in the state constitution of initiative, referendum, recall, direct election of senators, woman suffrage, and other reforms. Most of these proposals were included in the constitution that was submitted to Congress in 1912. President William Howard Taft insisted on removing the recall provision (because it would allow recall of judges) before he would approve it. It was removed, Taft signed the statehood bill on February 14, 1912, and state residents promptly put the provision back in.
In 1912 women gained suffrage (the vote) in the state, eight years before the country as a whole.