Logan County was a county in Idaho Territory and later the state of Idaho from 1889 to 1895. Logan County was created from parts of Alturas County by the Idaho Territorial Legislature in 1889 with Bellevue as its county seat. Six years later, the Idaho Legislature attempted to return Bellevue to Alturas County, but the plan was struck down by the state supreme court. In response on March 5, 1895, the Idaho Legislature combined Logan and Alturas Counties into a new county called Blaine. Two weeks later on March 18, the southern portion of the newly created Blaine County was split off to form Lincoln County with its county seat at Shoshone and Logan County ceased to exist. Bellevue became part of Blaine County.