In 1834 fur traders William Sublette and Robert Campbell established Fort William near the junction of the Laramie and North Platte rivers, within homelands used by Lakota, Cheyenne, Arapaho, and other Native nations. The log stockade served commerce in buffalo robes and manufactured goods. The American Fur Company bought the post, replaced it nearby with an adobe complex called Fort John, and integrated it into wider trading networks. Later usage favored the name Fort Laramie, derived indirectly from French Canadian trapper Jacques La Ramée.

As fur trade patterns changed, emigrant traffic increased along routes later called the Oregon, California, and Mormon Pioneer trails. Travelers crossed or followed the North Platte and stopped for repairs, supplies, mail, information, and rest. The United States Army purchased the post in 1849 and constructed a dispersed military station rather than another enclosed stockade. Buildings included officers' quarters, barracks, hospital, bakery, guardhouse, magazines, workshops, and stables. Old Bedlam, built in 1849, became a prominent officers' residence and is among Wyoming's oldest surviving military structures.

Fort Laramie supported military expansion and federal efforts to control travel and Native peoples. The 1851 and 1868 Fort Laramie treaties were negotiated in the region with representatives of numerous nations, but translation problems, differing concepts of land, incomplete representation, broken commitments, settler intrusion, and federal coercion undermined agreements. Troops operated during conflicts on the northern Plains and along emigrant routes. The fort's history therefore cannot be reduced to welcoming pioneers; it also documents dispossession, warfare, diplomacy, commerce, interdependence, and the agency of Native communities.

The army abandoned the post in 1890 and sold buildings and land at auction. Homesteaders adapted some structures as houses, barns, and storage, while others were dismantled or collapsed. Wyoming acquired the site in 1937, and it entered the National Park Service in 1938. Archaeology, documentary study, stabilization, and restoration followed. Some surviving buildings were returned toward selected nineteenth-century appearances and furnished for interpretation; foundations outline lost structures. What visitors see therefore mixes original military fabric, later alterations, restored rooms, reconstructed components, stabilized ruins, and open ground.

The National Park Service manages Fort Laramie National Historic Site with a visitor center, museum collections, trails, and accessible historic structures. Grounds are generally open without an entrance fee, subject to hours and seasonal conditions. Old Bedlam, the cavalry barracks, officers' quarters, ruins, and the river landscape help explain different periods, but modern interpretation increasingly centers Native histories alongside military and migration narratives. The site's preservation does not recreate a complete active fort. Instead, incomplete buildings and excavated footprints reveal how a commercial post became a federal installation, then private property, and finally a protected place of contested national memory.