c.10000 BC
Paleo-Indians enter the region, hunting big game such as woolly mammoth and giant ground sloth with stone-tipped spears.
AD 1
The earliest evidence of pottery dates to this period. Living in pithouses, people of the Cochise culture sustain themselves by hunting, gathering, and farming.
AD 50
Hohokam begin building irrigation canals near present-day Phoenix.
1064
Sunset Crater Volcano erupts. Sinagua farmers return to the region attracted by increased rainfall and moisture-retaining, ash-covered soil.
1250
Ancestral Pueblo people, or Anasazi, begin construction of Betatakin and Keet Seel in Tsegi Canyon, now part of Navajo National Monument.
1250–1450
Pueblo settlements in the Southwest are abandoned, due to drought, disease, or overuse of resources, and many Pueblo people in Arizona move to the Hopi mesas.
1250–1450
Athabascans migrate from the north, and later diverge into the Navajo and Apache tribes.
1540
Coronado expedition extends Spanish domain to the Southwest in futile search for reputed cities of gold.
1582
Antonio de Espejo finds some of the silver and copper deposits that would yield immense riches three centuries later.
1598
Juan de Oñate crosses Arizona and establishes the first European settlement in the Southwest, near Santa Fe, New Mexico.
Sinagua pueblo ruins at Tuzigoot National Monument.
Richard Nowitz/Apa Publications
1680
A sudden rebellion by Pueblo Indians costs the lives of more than 400 settlers in Arizona and New Mexico.
1687
Father Eusebio Francisco Kino begins the wide-ranging efforts that make this “Padre on Horseback” and founder of Tumacacori and San Xavier del Bac the most celebrated of the Spanish missionaries.
1751
Pima Revolt leads to establishment of a presidio at Tubac – which was moved to Tucson in 1776 – to protect missionaries and settlers from Indian attack.
1805
A Spanish military expedition into Canyon de Chelly results in the massacre of 115 Navajo, virtually all of them women, children, and old men.
1821
Mexico wins independence from Spain, thereby ruling Arizona.
1848
The United States, victorious in war with Mexico, takes over most of Arizona.
1854
The southern strip of Arizona is acquired from Mexico in the Gadsden Purchase.
1858
Discovery of gold nuggets in a prospector’s pan on the Gila River gives rise to Gila City, first of many Arizona mining boomtowns.
1859
The first of Arizona’s Indian reservations is established at Gila River. The greatest of all will be the Navajo Nation, covering nearly 16 million acres (7 million hectares), the largest reservation in the United States.
1863
President Abraham Lincoln signs a statute recognizing Arizona as a territory separate from New Mexico.
1869
Civil War veteran Major John Wesley Powell leads a pathfinding three-boat expedition down the Colorado River through the Grand Canyon.
1877
Arizona enters the era of transcontinental railroading with erection of a bridge over the Colorado River at Yuma for the Southern Pacific. Three years later, the line’s arrival in Tucson sets off a grand celebration.
1881
Wyatt Earp, two of his brothers, and Doc Holliday survive shootout at the O.K. Corral in Tombstone that becomes a Western legend.
1884
Two mining companies, Phelps Dodge and Copper Queen, tap into a rich vein in Bisbee, one of many deposits that will produce vast fortunes and make Arizona famous as one of the world’s greatest sources of copper.
1885
University of Arizona established.
1886
Surrender of Apache warrior Geronimo marks the end of Indian resistance.
1889
Phoenix becomes Arizona’s state capital.
1911
Dedication of Roosevelt Dam is first step in a federal irrigation project in the Salt River Valley that spurs development of the region.
1912
Arizona becomes the 48th state in the Union.
1917
About 1,200 striking copper miners and their supporters are removed from Bisbee by train and deposited in a desert hundreds of miles away as labor-management conflict intensifies.
1919
Grand Canyon National Park established.
1937
Architect Frank Lloyd Wright, consultant on the spectacular Arizona Biltmore Hotel in Phoenix, establishes a home and studio, Taliesin West, where he works until his death in 1959.
1941
The nation’s entry into World War II makes Arizona a busy location for defense purposes, stimulating population growth and transforming the state’s socioeconomic character.
1960
Sun City, a new community near Phoenix equipped with golf course and shopping center for “active” senior citizens, puts five model homes on display on January 1 and is besieged by thousands of prospective buyers.
1963
Arizona’s claim to a major portion of the water from the Colorado River is upheld by the United States Supreme Court.
1968
Congress approves the Central Arizona Project, a large-scale effort to deliver water to the state’s most populous region.
1983
Governor Bruce Babbitt calls out the National Guard after strikers shut down the Phelps Dodge mine in Morenci. The company eventually sells part of the mine and closes operations in Ajo and Douglas.
1990
London Bridge is rebuilt at Lake Havasu in western Arizona. The improbable import, rebuilt stone by stone, makes the reservoir area the most popular tourist attraction after the Grand Canyon.
2000
Arizona’s population reaches 5.1 million, an increase of 40 percent in 10 years; it is second only to Nevada as the fastest-growing in the nation.
2005
Grand Canyon’s El Tovar hotel observes its centennial on January 14.
2006–08
Forests around Sedona are struck by severe fires that force many residents to evacuate. Volunteer groups known as Minutemen protest illegal immigration and organize patrols of the US–Mexico border in Arizona and other western states.
2008
Arizona Senator John McCain loses the race for president to Senator Barack Obama.
2009
Jan Brewer is sworn in as Arizona governor following then-governor Janet Nepolitano’s appointment as head of Homeland Security in President Obama’s cabinet.
2010
Governor Brewer signs into law the nation’s toughest immigration law, aimed at identifying, prosecuting, and deporting illegal aliens. Controversy erupts nationwide. A year later the federal court of appeals upholds a ruling against the law, stating that it is a violation of the Constitution.
2011
Following the deadly shooting of six attendees at a meet-and-greet in Tucson by a disturbed young man, which left popular Congresswoman Gabrielle Giffords with serious head injuries, Governor Brewer vetoes a state law allowing concealed hand guns on campus. She also vetoes a law requiring proof of US citizenship for presidential candidates, a “birther law” promoted by the Tea Party, an activist right wing of the Republican party.
2013
US Supreme Court strikes down Arizona law aimed at preventing illegal immigrants from voting by demanding proof of US citizenship from all state residents when they register to vote in national elections.
2014
Arizona became the 31st state to legalize same-sex marriage.
2015
Museum of the West opens in downtown Scottsdale’s historic arts district, highlighting the area’s long Western history with revolving art exhibits in a large, modern building.