The Arapaho National Forest was established by Theodore Roosevelt on July 1, 1908. The Roosevelt National Forest, originally part of the Medicine Bow Forest Reserve, was first named the Colorado National Forest in 1910 and was renamed by President Herbert Hoover to honor President Theodore Roosevelt in 1932. The Pawnee National Grassland was transferred to the Forest Service from the Soil Conservation Service in 1954. It was designated a national grassland in 1960.