Fort Laramie (originally founded as
Fort William and then known for a while as
Fort John) was a significant 19th century trading post and diplomatic site located at the confluence of the
Laramie River and the
North Platte River in the upper
Platte River Valley in the eastern part of the
U.S. state of
Wyoming. Founded in the 1830s to service the overland fur trade during the middle 19th century, it sat at the bottom of the long climb leading to the best and lowest crossing point at
South Pass into western descending valleys and so was a primary stopping point on the
Oregon Trail. Along with
Bent's Fort on the
Arkansas River, the trading post and its supporting industries and businesses were the most significant
economic hub of commerce in the region. Fort William was a private fur trading post founded by
William Sublette in 1834. In 1841 it was purchased by the
American Fur Company and renamed Fort John. In 1849 it was purchased and its operations were taken over by the
United States Army to protect the many
wagon trains of
migrant travelers on the
Oregon Trail, and hence the subsidiary co-located northern
emigrant trails which split off further west such as the
California and
Mormon trails. The middle reaches of the Mormon trail stayed on the north banks of the Platte and North Platte River and merged with the other
emigrant trails heading west over the continental divide from Fort John-Laramie. The name Fort Laramie came into gradual use, likely as a convenient shortening of "Fort John at the Laramie River".