| County | County Seat | Date Formed | Original County | Coordinator |
| Ada | Boise State Capitol | December 22, 1864 | Boise | Sharon McConnel |
| Adams | Council | March 3, 1911 | Washington | Sharon McConnel |
| Alturas (defunct) | 1864-1895 | Original County | Judy White | |
| Bannock | Pocatello | March 6, 1893 | Bingham | Judy White |
| Bear Lake | Paris | January 5, 1875 | Oneida | Sharon McConnel |
| Benewah | St. Maries | January 23, 1915 | Kootenai | Sharon McConnel |
| Bingham | Blackfoot | January 13, 1885 | Oneida | Sharon McConnel |
| Blaine | Hailey | March 5, 1895 | Alturas | Sharon McConnel |
| Boise | Idaho City | February 4, 1864 | Original County | Sharon McConnel |
| Bonner | Sandpoint | February 21, 1907 | Kootenai | Judy White & Sharon McConnel |
| Bonneville | Idaho Falls | February 7, 1911 | Bingham | Sharon McConnel |
| Boundary | Bonners Ferry | January 23, 1915 | Bonner | Sharon McConnel |
| Butte | Arco | February 6, 1917 | Bingham, Blaine, Jefferson | |
| Camas | Fairfield | February 6, 1917 | Blaine | Chris Storey |
|
Canyon |
Caldwell | March 7, 1891 | Ada | Sharon McConnel |
| Caribou | Soda Springs | February 11, 1919 | Bannock | Sharon McConnel |
| Cassia | Burley | February 29, 1879 | Owyhee | Chris Storey |
| Clark | Dubois | February 1, 1919 | Fremont | Michael G. Shaw |
| Clearwater | Orofino | February 27, 1911 | Nez Perce | |
| Custer | Challis | January 8, 1881 | Alturas and Lemhi | Sharon McConnel |
| Elmore | Mountain Home | February 7, 1889 | Alturas | Sharon McConnel |
| Franklin | Preston | January 20, 1913 | Oneida | |
|
Fremont |
St. Anthony | March 4, 1893 | Bingham | Sharon McConnel |
| Gem | Emmett | March 15, 1915 | Boise and Canyon | Sharon McConnel |
| Gooding | Gooding | January 28, 1913 | Lincoln | Sharon McConnel |
| Idaho | Grangeville | February 4, 1864 | Original County | Sharon McConnel |
| Jefferson | Rigby | February 18, 1913 | Fremont | |
| Jerome | Jerome | February 8, 1919 | Gooding and Lincoln | Chris Storey |
| Kootenai | Coeur d'Alene | December 22, 1864 | Nez Perce | Judy White |
| Latah | Moscow | May 14, 1888 | Nez Perce | |
| Lemhi | Salmon | January 9, 1869 | Idaho | Sharon McConnel |
| Lewis | Nez Perce | March 30, 1911 | Sharon McConnel | |
| Lincoln | Shoshone | March 18, 1913 | Alturas and Blaine | Chris Storey |
| Madison | Rexburg | February 18, 1913 | Fremont | |
| Minidoka | Rupert | January 26, 1913 | Lincoln | Chris Storey |
| Nez Perce | Lewiston | February 4, 1864 | Original County | Sharon McConnel |
| Oneida | Malad | January 22, 1864 | Original County | |
| Owyhee | Murphy | December 31, 1863 | Original County | Sharon McConnel |
| Payette Co. historic post offices Payette Memorial Park Payette GenWeb |
Payette | February 28, 1917 | Canyon | Kerrie Taylor |
| Power | American Falls | January 30, 1913 | Bingham, Blaine, Oneida | |
| Shoshone | Wallace | February 4, 1864 | Original County | Randy Cummings |
| Teton | Driggs | January 26, 1915 | Madison | |
| Twin Falls | Twin Falls | February 21, 1907 | Cassia | Chris Storey |
| Valley | Cascade | February 26, 1907 | Idaho and Boise | Sharon McConnel |
| Washington | Weiser | February 20, 1879 | Boise | Sharon McConnel |
click to enlarge
Map Links -
Idaho State University Digital Atlas
Historic topo maps at Perry Castandeda Library, University of Texas
Perry-Castaneda Library Map Collection, University of Texas, home
Idaho at jhuapl.edu, Ray Sterner, John Hopkins University
David Ramsey Map Collection
Idaho at netstate.com/
USGS index of Geographic Names
original counties
Webspace for this site is generously provided by Genealogy Village and Access Genealogy
Copyright © 2013 - Sharon McConnel. All Rights Reserved.