Idaho in the Census

Contact:  Idaho State Coordinator

Contact: Idaho Assistant State Coordinator

• Oregon Territory was established in 1848 and included all of present-day Idaho.

• The area north of 46^o latitude was part of Spokane County, Washington.
• Some people living in the Bear Lake area were enumerated as part of Cache County, Utah.

• Idaho Territory was organized in 1863.
• For more information see Idaho Territorial Voters Poll Lists 1863, Transcribed, Edited and Indexed by Gene F. Williams, Boise, ID 1996.
• Click here to see the map and key from Gene's book, used by permission.
• 1. Shoshone, 2. Nez Perce, 3. Idaho,

4. Boise, 5. Missoula, 6. Other

• Parts of extreme southeast Oneida County were enumerated as part of Cache and Rich counties in Utah Territory.
• Unorganized Kootenai County was enumerated with Nez Perce County.

• Yellowstone National Park was created in 1872 cutting a small slice out of the extreme northeast corner of Oneida County. Any persons enumerated within this area are found in the Wyoming census from that year forward.

• Idaho became a state in July 1890.
• The federal census was lost for all counties.
• Logan and Alturas counties were abolished in 1895.

• Bannock, Bingham and Nez Perce Indian schedules were microfilmed immediately following Washington County.
• 1. Kootenai, 2. Latah, 3. Shoshone,

4. Nez Perce, 5. Idaho, 6. Lemhi, 
7. Washington, 8. Boise, 9. Custer, 
10. Fremont, 11. Canyon, 12. Ada, 
13. Blaine, 14. Bingham, 15. Lincoln, 
16. Owyhee, 17. Cassia, 18. Oneida, 
19. Bannock, 20. Bear Lake, 21. Elmore.

• An "every name" index exists for 1910, Idaho.
• 1. Bonner, 2. Kootenai, 3. Shoshone,

4. Latah, 5. Nez Perce, 6. Idaho, 
7. Washington, 8. Boise, 9. Custer, 
10. Lemhi, 11. Canyon, 12. Ada, 
13. Elmore, 14. Blaine, 15. Fremont, 
16. Lincoln, 17. Bingham, 18. Owyhee, 
19. Twin Falls, 20. Cassia, 21. Oneida, 
22. Bannock, 23. Bear Lake

• Most of the modern county lines were set by 1920, but please note the unfinished boundaries of Ada, Elmore, Owyhee, Custer, Butte, Bannock, Caribou, Franklin, & Oneida counties.