Idaho began as part of Oregon Territory. The counties in the panhandle became part of the Washington Territory in 1853. It became a separate territory in 1863, then encompassing most of what became Idaho, Montana, and Wyoming. Idaho was the 43rd state admitted to the Union, which occurred 3 July 1890.
Did you know
The Idaho State Archives (formerly the Idaho State History Society Public Archives and Research Library or PARL) is located at 2205 Old Penitentiary Road in Boise. They have a large collection of newspapers, photographs, and manuscripts relating to Idaho. The Research Center for the Archives is open Tuesday thru Saturday from 10 a.m. to 4 p.m. Their web site gives more information about their holdings.