Archive:Census Records, Montana
Eastern Montana was part of the Nebraska Territory 1854-1861 and the Dakota Territory 1861-1863; western Montana was part of the Oregon Territory 1848-1853, and the Washington Territory 1853-1863. From 1863 to 1864, all of Montana was part of the Idaho Territory. Montana was made a territory in 1864, and a state in 1889. Census records for Montana are available for the following years:
1860: East of the Continental Divide enumerated in the unorganized part of the Nebraska Territory and unorganized Dakota Territory; the west was enumerated in Spokane County, Washington Territory.