July 16, 1938 Presidential Proclamation No. 2292 Franklin D. Roosevelt established Fort Laramie National Monument containing 214.41 acres.
The lands and structures were donated to the United States by the Historical Landmark Commission of Wyoming in the public interest to reserve such lands and structures.
April 16,1960 Congress passed Public Law 86-444, an act to revise the boundaries and change the name of Fort Laramie National Monument to Fort Laramie National Historic Site.
November 10,1978 Public Law 95-625, the National Park and Recreation Act of 1978, revised the boundaries of Fort Laramie National Historic Site. Its current size is 833 acres.