Organization of the colony began in October 1869 by Nathan Meeker in order to establish a religiously-oriented utopian community of "high moral standards".
Union Colony was financially backed and promoted by New York Tribune editor, Horace Greeley, a prominent advocate of the settlement of the American West.
The homesteaded colony greatly advanced irrigation usage in present-day northern Colorado, demonstrating the viability of cultivation at a time when agriculture was emerging as a rival to mining as the principal basis for the territorial economy.
Horace Greeley had journeyed west in 1859 at the height of the Colorado Gold Rush, going from Denver to Fort Laramie via the Overland Stage Line before continuing on to California.
In 1869 Greeley sent Meeker, then employed as the agricultural editor of the Tribune, to the Colorado Territory to seek out a location for a colony to promote settlement in the West.
They purchased a tract of land in Weld County, near the confluence of the Cache la Poudre and South Platte Rivers and founded the settlement.