Idaho History 1800 to Present Facebook Group - Administered by Justin Smith and Skip Myers.
Idaho State Historical Society Reference Series - Former State Historian Merle Wells originated the Idaho State Historical Society Reference Series in the 1960s. Merle sought to have a handy series providing people with quick snapshots of different topics in Idaho history.
Idaho Yesterdays - Idaho Yesterdays is published by the Idaho State Historical Society with support from Idaho State University and the College of Social Sciences and Public Affairs at Boise State University. It is a peer-reviewed journal devoted to publishing current research on the history and culture of Idaho and Its region. Article index is available here.
David Rumsey map collection - An extensive collection of historical maps. This link takes you to a general search for "Idaho". Maps can be downloaded in high resolution or simply viewed online.
USGS historic maps - A useful resource for historic topographical maps of Idaho.
Idaho Historical Markers - An online version of the historical markers throughout Idaho - a joint project between the Idaho State Historical Society and Idaho Transportation Department.
Digital Library of Idaho - Extensive online collection of images from various Idaho government organizations.
Library of American - US Newspapers - Chronicling America is a large collection of historic newspapers available online.
Did You Know? - Pocatello history from local historian Arlen Walker.