Denver was founded in November, 1858 in traditional “wild west” fashion, the nearest railroad being 700 miles to the east. The hope of gold brought out the initial prospectors and the discovery of gold saw a mass movement of people resettle in what became Colorado Territory in 1861.
Both Golden and Colorado City served briefly as the capital for Colorado Territory before it was given to Denver in 1865, and it remained the capital when Colorado officially became a state on August 1, 1876.
In a thirty year span of time, Denver jumped from a small band of prospectors to 4,731 people in 1870, to a population of 35,628 by 1880, and surging to 106,713 by 1890, making it the fifth largest city west of the Mississippi. This massive increase is attributed to the growth of the mining industry as well as the building of The Denver Pacific, Kansas Pacific, and Colorado Central Railroads.
The growth of the gold and silver rushes caused obvious tension between the settlers and the Native Americans already living there, leading to the Colorado War (or the Arapaho-Cheyenne War between the United States and the Kiowa, Comanche, Araphaho, and Cheyenne tribes from 1863-1865. The end result involved the brutal killing and mutilation of many Indians, including women and children, and the removal and resettlement of the remaining Native American population to what is now present day Oklahoma.
The population surge also ensured an economic boom for both the city of Denver and the state of Colorado. Agriculture and manufacturing became big, thriving industries here. A silver crash in 1893 caused a depression to hit, though, putting an end to the development. About a decade later Denver started growing again, but much more slowly than before.