The National Grasslands resulted from a combination of human and natural factors. Now managed as an integral pan of the National Forest System, lands making the National Grasslands were for the most part privately owned until the 1930's.

In the late 1800's and early 1900's thousand of people, encouraged by promotional campaigns and offers of free land, moved to the Great Plains. Further inspired by a series of wet years and a market demand for wheat and red meat during and after World War I, homesteaders had cultivated and/or heavily grazed most of the Great Plains by the mid 1920's. Much of the land was marginal should never have been plowed. Resulting from depleted croplands, overstocked rangelands, and severe droughts of the 1930's an estimated two and a half million people abandoned their small farms and ranches on the Plains.

To help lessen the effects of the Great Depression the federal government began to purchase identified submarginal lands with goal of controlling erosion, producing more forage, and ensuring rural economic stability for the remaining residents. Between 1933 and 1946, 11.3 million acres in 45 states were purchased and called Land Utilization (L-U) projects.

The U.S. Department of Agriculture became the custodian of the lands in 1937 as directed by Bankhead-Jones Farm Tenant Act, with the Forest Service assigned responsibility in 1954. Nearly 4 million acres were designated as National Grasslands in 1960. Today there are 20 National Grasslands that are part of the National Forest System.