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List of territorial claims and designations in Colorado
Geographic chronology of Colorado / From Wikipedia, the free encyclopedia
The area currently occupied by the U.S. State of Colorado has undergone numerous changes in occupancy, territorial claims, and political designations. Paleoamericans entered the region about 11,500 BCE,[1] although new research indicates the region may have been visited much earlier.[2] At least nine Native American nations have called the area home. Although Europeans may have entered the region as early as 1540,[3] the first European fort[lower-alpha 1] was not constructed until 1819,[4] and the first European town[lower-alpha 2] was not established until 1851,[5] primarily due to the opposition of the Ute people. Spain,[6] France,[7] Mexico,[8] and the Republic of Texas[9] have all claimed areas of future state. The United States first claimed an eastern portion of the future state with the Louisiana Purchase of 1803.[10][lower-alpha 3] The United States surrendered the portion of the region south and west of the Arkansas River to the Spanish Empire with the Adams–Onís Treaty in 1821.[11][lower-alpha 4][lower-alpha 5] The United States completed its acquisition of the region with the Treaty of Guadalupe Hidalgo that ended the Mexican–American War in 1848.[12] The United States created the free Territory of Colorado in 1861 following the Pikes Peak Gold Rush.[13] The Territory fought for the Union during the American Civil War[14] despite many of its founders being natives of slave states or territories.[15] The Territory of Colorado joined the Union as the State of Colorado in 1876, the centennial year of the United States.[16]
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