Colorado (or ) is a U.S. state encompassing most of the Southern Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains. Colorado is part of the Western United States, the Southwestern United States, and the Mountain States. Colorado is the 8th most extensive and the 22nd most populous of the 50 United States. The United States Census Bureau estimates that the population of Colorado was 5,187,582 on July 1, 2012, an increase of +3.15% since the 2010 United States Census.
The state was named for the Colorado River, which Spanish explorers named the Río Colorado for the silt the river carried from the mountains. On August 1, 1876, U.S. President Ulysses S. Grant signed a proclamation admitting Colorado to the Union as the 38th state. Colorado is nicknamed the "Centennial State" because it became a state in the centennial year of the United States Declaration of Independence.
Colorado is bordered by the northwest state of Wyoming to the north, the Midwest states of Nebraska and Kansas to the northeast and east, on the south by New Mexico and Oklahoma, on the west by Utah, and Arizona to the southwest. The four states of Colorado, New Mexico, Utah, and Arizona meet at one common point known as the Four Corners, which is known as the heart of the American Southwest. Colorado is noted for its vivid landscape of mountains, forests, high plains, mesas, canyons, plateaus, rivers, and desert lands.
The region that is today the state of Colorado has been inhabited by Native Americans for more than 13,000 years. The Lindenmeier Site in Larimer County contains artifacts dating from approximately 11200 BC to 3000 BC. The eastern edge of the Rocky Mountains was a major migration route that was important to the spread of early peoples throughout the Americas. The Ancient Pueblo Peoples lived in the valleys and mesas of the Colorado Plateau. The Ute Nation inhabited the mountain valleys of the Southern Rocky Mountains and the Western Rocky Mountains, even as far east as the Front Range of present day. The Apache and the Comanche also inhabited the Eastern and Southeastern portions of the state as well. The Arapaho Nation and the Cheyenne Nation moved west to hunt across the High Plains at times as well.
The United States acquired a territorial claim to the eastern flank of the Rocky Mountains with the Louisiana Purchase from France in 1803. This U.S. claim conflicted with the claim of Spain to the upper Arkansas River Basin as the exclusive trading zone of its colony of Santa Fé de Nuevo Méjico. Zebulon Pike led a U.S. Army reconnaissance expedition into the disputed region in 1806. Colonel Pike and his men were arrested by Spanish cavalrymen in the San Luis Valley the following February, taken to Chihuahua, and then expelled from Mexico the following July.
The United States relinquished its claim to all land south and west of the Arkansas River and south of 42nd parallel north and west of the 100th meridian west as part of its purchase of Florida from Spain with the Adams-Onís Treaty of 1819. The treaty took effect February 22, 1821. Having settled its border with Spain, the United States admitted the southeastern portion of the Territory of Missouri to the Union as the state of Missouri on August 10, 1821. The remainder of the Missouri Territory, including what would become northeastern Colorado, became unorganized territory, and would remain so for 33 years over the question of slavery. After 11 years of war, Spain finally recognized the independence of Mexico with the Treaty of Córdoba signed on August 24, 1821. Mexico eventually ratified the Adams-Onís Treaty in 1831. The Texian Revolt of 1835–1836 fomented a dispute between the United States and Mexico which eventually erupted into the Mexican-American War in 1846. Mexico surrendered its northern territory to the United States with the Treaty of Guadalupe Hidalgo at the conclusion of the war in 1848.
The gold seekers organized the Provisional Government of the Territory of Jefferson on August 24, 1859, but this new territory failed to secure approval from the Congress of the United States embroiled in the debate over slavery. The election of Abraham Lincoln for the President of the United States on November 6, 1860, led to the secession of nine southern slave states and the threat of civil war among the states. Seeking to augment the political power of the Union states, the Republican Party dominated Congress quickly admitted the eastern portion of the Territory of Kansas into the Union as the free State of Kansas on January 29, 1861, leaving the western portion of the Kansas Territory, and its gold-mining areas, as unorganized territory.
Thirty days later on February 28, 1861, outgoing U.S. President James Buchanan signed an Act of Congress organizing the free Territory of Colorado. The original boundaries of Colorado remain unchanged today. The name Colorado was chosen because it was commonly believed that the Colorado River originated in the territory. In 1776, Spanish priest Silvestre Vélez de Escalante recorded that Native Americans in the area knew the river as for the red-brown silt that the river carried from the mountains. In 1859, a U.S. Army topographic expedition led by Captain John Macomb located the confluence of the Green River with the Grand River in what is now Canyonlands National Park in Utah. The Macomb party designated the confluence as the source of the Colorado River.
On April 12, 1861, South Carolina artillery opened fire on Fort Sumter to start the American Civil War. While many gold seekers held sympathies for the Confederacy, the vast majority remained fiercely loyal to the Union cause.
In 1862, a force of Texas cavalry invaded the Territory of New Mexico and captured Santa Fe on March 10. The object of this Western Campaign was to seize or disrupt the gold fields of Colorado and California and to seize ports on the Pacific Ocean for the Confederacy. A hastily organized force of Colorado volunteers force-marched from Denver City, Colorado Territory, to Glorieta Pass, New Mexico Territory, in an attempt to block the Texans. On March 28, the Coloradans and local New Mexico volunteers stopped the Texans at the Battle of Glorieta Pass, destroyed their cannon and supply wagons, and ran off 500 head of their horses and mules. The Texans were forced to retreat to Santa Fe. Having lost the supplies for their campaign and finding little support in New Mexico, the Texans abandoned Santa Fe and returned to San Antonio in defeat. The Confederacy made no further attempts to seize the Southwestern United States.
In 1864, Territorial Governor John Evans appointed the Reverend John Chivington as Colonel of the Colorado Volunteers with orders to protect white settlers from Cheyenne and Arapaho warriors who were accused of stealing cattle. Colonel Chivington ordered his men to attack a band of Cheyenne and Arapaho encamped along Sand Creek. Chivington reported that his troops killed more than 500 warriors. The militia returned to Denver City in triumph, but several officers reported that the so-called battle was a blatant massacre of Indians at peace, that most of the dead were women and children, and that bodies of the dead had been mutilated and desecrated in hideous manner. Three U.S. Army inquiries condemned the action, and incoming President Andrew Johnson asked Governor Evans for his resignation, but none of the perpetrators was ever punished.
The United States Congress passed an enabling act on March 3, 1875, specifying the requirements for the Territory of Colorado to become a state. On August 1, 1876 (28 days after the Centennial of the United States), U.S. President Ulysses S. Grant signed a proclamation admitting Colorado to the Union as the 38th state and earning it the moniker "Centennial State".
The discovery of a major silver lode near Leadville in 1878, triggered the Colorado Silver Boom. The Sherman Silver Purchase Act of 1890 invigorated silver mining, and Colorado's last, but greatest, gold strike at Cripple Creek a few months later lured a new generation of gold seekers. Colorado women were granted the right to vote beginning on November 7, 1893, making Colorado the second state to grant universal suffrage and the first one by a popular vote (of Colorado men). The repeal of the Sherman Silver Purchase Act in 1893 led to a staggering collapse of the mining and agricultural economy of Colorado, but the state slowly and steadily recovered.
Colorado became the first western state to host a major political convention when the Democratic Party met in Denver in 1908. By the U.S. Census in 1930, the population of Colorado first exceeded one million residents. Colorado suffered greatly through the Great Depression and the Dust Bowl of the 1930s, but a major wave of immigration following World War II boosted Colorado's fortune. Tourism became a mainstay of the state economy, and high technology became an important economic engine. The United States Census Bureau estimated that the population of Colorado exceeded five million in 2009.
Three warships of the U.S. Navy have been named the USS Colorado. The first USS Colorado was named for the Colorado River. The later two ships were named in honor of the state, including the battleship USS Colorado which served in World War II in the Pacific beginning in 1941. At the time of the Attack on Pearl Harbor, this USS Colorado was located at the naval base in San Diego, Calif. and hence went unscathed.
Note: Although part of Colorado was acquired as early as the Louisiana Purchase of 1803, it had no organized government until 1850, when parts of the present State were included in New Mexico and Utah Territories. Colorado was established as a territory in 1861 with its present boundaries, from parts of Kansas, Nebraska, New Mexico, and Utah Territories. The 1860 population is the total enumerated within the 1861 boundaries. Colorado was admitted as a State on August 1, 1876. Present-day Colorado had no census coverage in 1850, and none in 1860 for the portion taken from Utah Territory.. Population shown for 1860 is that enumerated in the area organized in 1861 as Colorado Territory from parts of Kansas, Nebraska, New Mexico, and Utah Territories. This total was not reported by county.. Total for 1890 includes population (1,051) of the Ute (Southern Ute) Indian Reservation, not reported by county.
Births, Marriages, and Deaths
Ancestry.com has a collection of marriage records from Mesa, Arapahoe, and Boulder counties at Colorado Marriages, 1859-1900.
FamilySearch.org has a variety of collections available for free online:
See the Colorado Research Guide
Outstanding guide to Colorado family history and genealogy (FamilySearch Research Wiki). Birth, marriage, and death records, wills, deeds, county records, archives, Bible records, cemeteries, churches, censuses, directories, immigration lists, naturalizations, maps, history, newspapers, and societies.