Green River County, Utah Genealogy

United States Utah  Green River County

Green River County, Utah Territory was an extinct county created 3 March 1852 in the northeast corner of Utah Territory on land that eventually became parts of Utah, Wyoming, and Colorado.

The only residents of this county on the 1856 Utah territorial census and Utah 1860 federal census were listed at Fort Bridger on the Oregon-California-Mormon Trail in present-day Wyoming.

In 1861 the U.S. Congress began carving pieces off of Utah Territory to give to other territories. Parts of Utah Territory were given to form parts of Colorado, Nebraska (later Wyoming), and all of the original Nevada Territory. Two of these giveaways directly affected Green River County. Utah Territory south of 41º and east of 109º was given to Colorado Territory which included about half of Green River County. The Green River County land north of 41º and east of 110º was given to Nebraska Territory (later Wyoming) leaving Green River County less than a tenth of its previous size.