Colorado: A Historical Timeline

PRIOR TO 1500 PRE-EUROPEAN SETTLEMENT
1500 BCE	The earliest inhabitants of the Colorado area, primarily nomadic hunters, arrive. Gradually they develop farming practices, raising corn and squash.
1200– 1300 CE	The Pueblo Native Americans build Cliff Palace, the largest cliff dwelling in North America, at Mesa Verde. It is. By the end of the 13th century, they have abandoned their cliff dwellings and moved south.
1500	When Spanish explorers come to the area, they encounter many different tribes. The Ute inhabit the valleys of the southern Rocky Mountains, while the Comanche, Cheyenne, Arapaho, and Kiowa live in the Great Plains region.
1500–1800 EARLY EUROPEAN EXPLORATION
1598	(July 11) Spanish conquistador Juan de Oñate founds what will become the New Spain province of Santa Fé de Nuevo Méjico, which extends into the Colorado area.
1706	Juan de Ulibarri claims the region for Spain.
1765	Juan Maria Rivera leads a Spanish expedition through the region in search of gold and silver.
1776	Friars Escalante and Dominguez traverse what is now western Colorado while seeking a route from Santa Fe to the California missions. They explore as far north as the White River in Rio Blanco County.
1778	Spanish explorer Juan Bautista de Anza leads a punitive expedition across New Mexico and Colorado against the Comanche Native Americans. His forces corner and kill the Comanche chief and other leaders at what becomes Rye, Colorado.
1787	Juan Bautista de Anza establishes the San Carlos settlement near present-day Pueblo, trading with the Native American population. It is the only Spanish settlement north of the Arkansas River, but it soon fails.
1800–1849 WESTWARD EXPANSION
1800	Spain cedes a vast area of land, including part of Colorado, to Napoleon Bonaparte of France.
1803	The U.S. acquires most of eastern Colorado (and 13 other future U.S. states) from France as part of the Louisiana Purchase. President Thomas Jefferson agrees to the purchase price of 78 million francs ($15,000,000) from French head of state Napoleon Bonaparte. The purchase is lauded by supporters and savaged by critics of Jefferson. It more than doubles the size of the United States and is a defining moment in the expansion of U.S. territory.
1806	American lieutenant Zebulon Montgomery Pike explores the southwestern portion of the Louisiana Territory. Although his attempt to scale Pikes Peak, the 14,110-foot peak that now bears his name, is unsuccessful, he does publish a report that attracts interest to the area. In the report, Pike notes that it is unlikely the summit will ever be scaled.
1820	Numerous Native American tribes still thrive in the Colorado area. The Ute live in the mountains, the Cheyenne and Arapahoe reside on the plains, and the Kiowa and Comanche live south of the Arkansas River. The Pawnee tribe hunts buffalo along the Republican River, and the Sioux hunt the outskirts of the Cheyenne and Arapahoe lands. (July 14) Edwin James and Major Stephen H. Long prove Zebulon Montgomery Pike wrong when they become the first to successfully climb to the summit of Pikes Peak.
1832	One of the most important trading posts in the West, Bent’s Fort is built near present-day La Junta to trade buffalo skins with the Cheyenne and Arapaho Native Americans. The post is mysteriously destroyed in 1849.
1836	Texas becomes an independent republic and lays claim to a narrow strip of territory extending into Colorado.
1842	Lieutenant John Fremont undertakes the first of his five exploratory trips into the Rocky Mountains to find a suitable railroad route. His last expedition, in 1853, takes him through the San Luis Valley and into Gunnison River country.
1848	(February 2) As part of the Treaty of Guadeloupe Hidalgo, Mexico cedes the area of Colorado not already acquired by the Louisiana Purchase to the U.S. at the end of the Mexican-American War. This opens the southern Rocky Mountains to American settlement.
1849–1876 AN EMERGING TERRITORY
1849	Gold seekers bound for California pan small amounts of gold at the foot of the Rocky Mountains in what is now Colorado. Rumors of Rocky Mountain gold spread, and numerous prospectors soon arrive in the area.
1850	As part of the Compromise of 1850, Texas drops all claims to portions of Colorado.
1851	The first permanent non–Native American settlement in Colorado is founded at Conejos in the San Luis Valley. Fort Massachusetts is established to protect settlers from Native American attacks in retaliation for encroachment on Native land.
1853	Captain John Gunnison leads an expedition across southern and western Colorado to survey a route for a Pacific railroad between the 38th and 39th parallels. The town of Gunnison and the Gunnison River in the Tomichi Valley are named in his honor.
1858	(July) William Green Russell leads a party of prospectors from the state of Georgia to discover gold in what is now downtown Denver, marking the beginning of the Pikes Peak Gold Rush.
1859	(May 6) John Gregory discovers "The Gregory Lode" in a gulch near Central City. Within two weeks, the gold rush is well underway, and within two months the population booms. The area comes to be known as the "Richest Square Mile on Earth." Under the banner of the "Pikes Peak or Bust" slogan, gold seekers known as "’59ers" flock to Colorado. Through February 1861, roughly 100,000 prospectors try to strike it rich in one of the largest gold rushes in U.S. history. (October 24) The provisional government of the Territory of Jefferson is established. Encompassing all of modern-day Colorado and several other future U.S. states, the territory is never officially recognized by the U.S. government.
1861	(February 28) President James Buchanan signs the Organic Act, which establishes the Territory of Colorado, solidifying Union control of the Rocky Mountains. While the Territory of Jefferson is dissolved, the new Colorado Territory adopts many of its laws.
1862	(March 26–28) The Battle of Glorieta Pass is waged in New Mexico. Colorado troops aid in defeating the Confederate Army, and the Union continues to hold possession of the West at the height of the Civil War.
1863	Tensions between Native American and white settlers escalate. Plains Native Americans begin attempting to drive settlers from their hunting lands on the eastern slopes.
1864	In retaliation for a Native American attack on a party of immigrants near Denver, 750 members of a Colorado militia unit attack an unsuspecting village of Cheyenne and Arapahoe on Sand Creek. Three hundred Native American men, women, and children are killed in the Sand Creek Massacre. Camp Collins is established to protect travelers on the Overland Trail.
1865	Native American attacks continue along trail peaks. The U.S. establishes Fort Morgan for protection from Native American attack. Food becomes scarce and expensive.
1868	(September 17–19) In eastern Colorado, 500 Sioux and Cheyenne attack Beecher Island, engaging 50 volunteer militia members. The attack is in retaliation for military attacks against the tribes and encroaching white settlements. Although outmatched in number, the militia emerges victorious, killing Cheyenne war leader Roman Nose.
1870	The Denver and Pacific Railroad is constructed to connect Denver with the Union Pacific at Cheyenne, Wyoming. The Kansas Pacific Railroad enters Colorado over the Missouri River.
1876–1930 THE STATE OF COLORADO
1876	(August 1) Colorado becomes the 38th state admitted to the Union.
1879	Silver is discovered in Leadville, resulting in the Colorado Silver Boom. Over $82,000,000 worth of the metal is mined throughout the 1880s, resulting in a large increase in both population and wealth. The boom ends in 1893 with the collapse of silver prices.
1881	The Ute tribes are removed from Colorado and forced onto reservations.
1888	A band of Utes from Utah wage the last Native American raid in Colorado. They are defeated and returned to the reservation.
1893	(November 7) Following Wyoming, Colorado becomes the second state in the nation to extend voting rights to women.
1894	Cattlemen on the Roan Plateau drive 4,000 sheep off the cliffs in the Peach Day Massacre. The dispute is over the grazing rights between cattle and sheep operators, and the conflicts continue well into the 1930s.
1900	Gold production peaks at more than $20,000,000 annually at Cripple Creek, the second richest gold camp in the world.
1905	(March 17) Alva Adams, James H. Peabody, and Jesse McDonald vie to be Colorado’s governor during a political squabble. Adams wins the election, but the legislature forces him to step down. It declares his opponent, James Peabody, governor on the condition that he immediately resign so his lieutenant governor, Jesse McDonald, can take office.
1914	(April 20) Twenty people (11 of them children) are killed in the hostilities between striking coal miners and the Colorado National Guard during the Ludlow Massacre near Trinidad. It is the most violent event of the 14-month Colorado Coal Strike. In late April, federal troops move into southern Colorado to restore peace.
1918	Agricultural production increases dramatically to aid the World War I effort. Dry lands are plowed to produce wheat.
1920	The Ku Klux Klan establishes a presence in Colorado. By the 1930s, Colorado has the largest and most influential Klan following of any state west of the Mississippi River.
1927	(November 21) State police and company guards, some armed with machine guns, attack striking coal miners in the town of Serene in the Columbine Mine Massacre.
1933	Federal legislation allows all Colorado coal miners to join unions without fear of retaliation.
1941	The U.S. enters World War II. During the course of the war, Colorado’s agriculture industry experiences its greatest production in history.
1942	(August) The federal government opens Camp Amache in southeastern Colorado in order to inter Japanese-Americans, who are relocated from their homes on the West Coast.
1950–PRESENT MODERN COLORADO
1952	The Rocky Flats Plant near Denver begins operations, producing nuclear weapons and weapons parts specifically for use in the hydrogen bomb. It remains a controversial facility until its closure in 1992.
1957	A fire at the Rocky Flats Plant releases radioactive materials into the atmosphere and results in close to a million dollars in damage. Radioactive leaks and contamination continue in separate incidents at the site for the next several decades.
1958	After being relocated from the Lowry Air Force Base, the Air Force Academy is built near Colorado Springs. The first woman joins in 1976. Colorado suffers from a grasshopper plague, and a special session of the state legislature is called to solve the problem.
1970s	The oil, coal, and solar energy industries in Colorado boom.
1974	Desegregation of schools begins in Denver.
1976	Colorado becomes the only U.S. state in history to turn down the Olympic Games when a measure to do so is defeated by 62 percent of state voters.
1998	(October 12) Matthew Shepard, a gay student at the University of Wyoming, dies at Fort Collins after being tortured and lashed to a fence near Laramie. The incident sparks national, and even international, attention and outrage and leads to increased calls for hate crime legislation.
1999	(April 20) Two Columbia High School students use guns and explosives to kill 12 other students and one teacher before taking their own lives in the Columbine High School Massacre. The event brings international attention to the small Colorado town and further inflames debates on gun control and youth violence.
2001	The U.S. Congress passes the Rocky Flats National Wildlife Refuge Act, setting aside 6,400 acres (4.0 km2) of the former Rocky Flats Plant location as a wildlife preserve. In 2007 the EPA announces the site has been decontaminated, and the next month another 4,000 acres is added to the refuge.
2006	(December 31) A winter storm dumps three feet of snow across the plains, and Governor Bill Owens declares a statewide emergency. In January hundreds of hay bales fall from the skies across Colorado as military helicopter and cargo plane crews deliver food to cattle that have been stranded due to the heavy snow.
2007	(March 20) The Mathew Shepard Act—legislation that would expand the 1969 hate-crime laws to include crimes motivated by a victim’s gender, sexual orientation, gender identity, or disability—is introduced in Congress.