Admitted to the Union on August 1, 1876 as the 38th state. Prior to statehood, in the 1860 census what is now present-day Colorado lay in four territorial jurisdictions, three of which are extant: Kansas Territory, Nebraska Territory, and New Mexico Territory. The Colorado area of Utah Territory was unsettled by whites and was not enumerated in 1860. Since there are numerous Park/e/s listings in both Kansas and Nebraska Territories in 1860, those will be included here.

  • 1870—1940 federal censuses extant for all counties except for 1890.
  • 1885 state census extant for all counties except Fremont and Garfield.
Adams Alamosa Arapahoe Archuleta
Baca Bent Boulder Broomfield
Chaffee Cheyenne Clear Creek Conejos
Costilla Crowley Custer Delta
Denver Dolores Douglas Eagle
Elbert El Paso Fremont Garfield
Gilpin Grand Gunnison Hinsdale
Huerfano Jackson Jefferson Kiowa
Kit Carson Lake La Plata Larimer
Las Animas Lincoln Logan Mesa
Mineral Moffat Montezuma Montrose
Morgan Otero Ouray Park
Phillips Pitkin Prowers Pueblo
Rio Blanco Rio Grande Routt Saguache
San Juan San Miguel Sedgwick Summit
Teller Washington Weld Yuma