When Did Colorado Join the Union?

The Colorado State Capitol.
The Colorado State Capitol.

Colorado is an American state that is located in the western part of the country. Colorado is bordered by Utah, New Mexico, Oklahoma, Kansas, Nebraska, and Wyoming. Colorado touches Arizona at the Four Corners area. Colorado is the eighth biggest American state which occupies an area of about 104,094 sq miles. It is the twenty-first most highly populated U.S. state with over 5,695,564 residents. Colorado became the 38th state on August 1, 1876. 

When Was Colorado Founded?

Colorado was the thirty-eighth state to be admitted into the Union a century after the U.S. Declaration of Independence was signed. The state of Colorado gained statehood in 1876 after President Grant signed a proclamation that admitted the territory into the Union. Colorado was initially part of the Spanish Province of New Mexico. The U.S. government acquired claim over the region with the 1803 Louisiana Purchase from the French. Their claim conflicted with the Spanish Empire’s claim of Upper Arkansas-River Basin as its colony’s trading zone. The Americans relinquished their claim after they purchased Florida from the Spanish Empire in 1819.


The state is known for its diverse geography that includes deep canyons, deserts with big dunes, high plains, and alpine mountains. Initially, the U.S. government defined the borders of Colorado territory using the longitude and latitude lines. Currently, the state’s borders are defined by 697 straight border lines and 697 boundary markers. Utah, Wyoming, and Colorado are the only American states whose borders have no natural feature and are defined by straights lines. The 14,440 ft Mount Elbert is the highest point in the Rocky Mountains and Colorado. 


The population of Colorado grew by 13.25% from 2010 (5,029,196) to 2018 (5,695,564). Denver is the capital and most populous city in Colorado with the Greater-Denver Metropolitan region having over 3,515,374residents in 2017. The Greater Denver Metropolitan is located in the Front-Range Urban Corridor that is occupied by over 5million Coloradans. The fastest growing counties in Colorado are Weld and Douglas. The racial composition of all the Coloradans in 2010 was whites (81.3%), Latino Americans (20.7%), Black Americans (4%), and Asians (2.8%) among others. The largest ancestry groups in the state are English (12%), Irish (12%), Mexicans (18%), and German (22%). The highest proportion of Hispanic Americans is found in Colorado Springs, Metropolitan Denver, Pueblo and Greeley. Some of the largest Black American communities are in Denver.


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