Colorado Territory

The Territory of Colorado was an organized incorporated territory of the United States that existed from February 28, 1861, until August 1, 1876, when it was admitted to the Union as the 38th State of Colorado.

The territory was organized in the wake of the Pike's Peak Gold Rush of 1858–1862, which brought the first large concentration of white settlement to the region. The organic legislative act creating the free Territory of Colorado was passed by the United States Congress and signed by 15th President James Buchanan into law on February 28, 1861. This was during the onset of the American Civil War of April 1861 to June 1865. The boundaries of the newly designated Colorado Territory were essentially identical with those of the modern State of Colorado, with lands taken from the four surrounding previous Federal territories of Nebraska, Kansas, New Mexico, and Utah established during the 1850s. The organization of the new territory helped solidify Union control over the mineral-rich area of the western Rocky Mountains. Statehood was regarded as fairly imminent with the expected growth in the constantly westward moving population, but the local territorial ambitions for full statehood were thwarted at the end of the war in 1865 by a constitutional veto by newly sworn in 17th President Andrew Johnson (1808–1875, served 1865–1869), who was a War Democrat who succeeded to the office after briefly only serving one month as Vice President after Lincoln's assassination that April. Statehood for the territory was a recurring issue during the subsequent Ulysses S. Grant presidential administration, with Republican 18th President Grant advocating statehood against a less willing Congress during the following post-war Reconstruction era (1865–1877). After a long constant lobbying campaign, the old Colorado Territory finally ceased to exist after only 15 years when the State of Colorado was admitted to the Union as the 38th state during the American Centennial celebration in August 1876.

East and West of the Continental Divide, which split the North American continent and the Rocky Mountains, plus the new territory which included the western portion of the previous Kansas Territory, as well as some of the southwestern decade-old Nebraska Territory, and a small parcel of the northeastern corner of the New Mexico Territory. On the western side of the Divide, the territory included much of the eastern older Utah Territory, all of which besides its substantial while Mormon / L.D.S. population especially around the capital of Salt Lake City, was strongly controlled by the Ute and Shoshoni native tribes The Eastern Plains were held much more loosely by the intermixed Cheyenne and Arapaho, as well as by the Pawnee, Comanche and Kiowa. In 1861, ten days before the establishment of the Federal territory, the Arapaho and Cheyenne agreed with the United States government in the East in Washington, D.C. to give up most their areas of the Great Plains to white settlement but were allowed to live in their larger traditional areas, so long as they could tolerate homesteaders near their camps. By the end of the American Civil War in 1865, the Native American presence had been largely reduced or pacified through military action or peace treaties on the High Plains.

The land that eventually became the Colorado Territory fell under the jurisdiction of the United States in three separate stages: the Louisiana Purchase in 1803 (as adjusted by the 1819 Adams–Onis Treaty), then the Annexation of Texas in 1845, and finally the Mexican Cession in 1848. The land claims of Texas were initially controversial. The border between the U.S. and Mexico was redrawn in 1848 with the Treaty of Guadalupe Hidalgo at the end of the Mexican–American War, and the final borders of the state of Texas were established by the Congressional Compromise of 1850.

The land that was eventually defined as the Colorado Territory was home to a number of indigenous civilizations. The Ute lived across both Western Colorado and the eastern high plains. The Anasazi lived in the southwestern, southern, and parts of southeastern Colorado. The Comanche and Jicarilla Apache lived in the area that would become the southeastern portions of the Territory. The Arapaho and Cheyenne also had a presence in the eastern and northeastern plains of the area at times.

The earliest explorers of European extraction to visit the area were Spanish explorers such as Coronado, although the Coronado expedition of 1540–42 only skirted the future border of the Colorado Territory to the south and southeast. In 1776, Francisco Atanasio Domínguez and Silvestre Vélez de Escalante explored southern Colorado in the Dominguez-Escalante Expedition.

Other notable explorations included the Pike Expedition of 1806–07 by Zebulon Pike, the journey along the north bank of the Platte River in 1820 by Stephen H. Long to what came to be called Longs Peak, the John C. Frémont expedition in 1845–46, and the Powell Geographic Expedition of 1869 by John Wesley Powell.

In 1779, Governor de Anza of New Mexico fought and defeated the Comanches under Cuerno Verde on the Eastern Slope of Colorado, probably south of Pueblo. In 1786, de Anza made peace with the Comanches, creating an alliance against the Apaches.