Mountain Men and Life in the Rocky

Subject Guide


Mountain West

Malachite’s Big Hole

Fort Jackson:

Although nothing is known of the structure of Fort Jackson, this post is of great importance because, unlike the other posts, some of the business records have been preserved.  Fort Jackson was constructed sometime in the spring of 1837 by Pratte, Choteau and Co (aka the American Fur Company) in response to the construction of Fort Vasquez by Louis Vasquez and Andrew Sublette.  The American Fur Company considered this area to be part of the trading territory within the sphere of influence of their Fort Laramie (Fort William) to the north. Two of the company's most able traders, Peter Sarpy and Henry Fraeb were sent to manage the operation. This was a typical response to opposition outfits by the American Fur Company which was simply to overwhelm the competition by under pricing their trade goods, bidding over market prices for furs and if necessary by providing large quantities of alcohol. 

By 1837 the number of beaver being caught was in decline, as was the price being paid for beaver skins.  Being located on the prairie, trade at this fort, as well as the others, was mainly in buffalo robes.  According to business records (Reference Guy Peterson 1982) during the winter of 1837-38 a total of 2,761 buffalo robes, then valued at $9,319 were taken in, whereas only 53 beaver pelts, valued at $193 were obtained. 

Business at the fort was not conducted by simply waiting passively for Indians to come in and trade.  Rather the fort served as a base of operations for small trading parties which were sent out to intercept the Indians in their camps and villages hopefully to obtain all their trade before any of the competitors.   This was probably the standard business model for these forts.  Although I have not found documentation specifically for these Forts Lancaster, Fort George and Fort Vasquez, it is known that the American Fur Company (Larpenteur, Chardon) Lancaster Lupton (Rufus Sage) and the Bent, St. Vrain & Company (Wootton, Garrard) also sent out similar small trading parties from other posts that they operated.  

Records survive for one such trading party sent out Fort Jackson on December 2, 1837.  James C Robertson, a company trader, took an outfit supplied with $937 worth of goods down to the Arkansas River to trade with the Indians there, probably in the Big Timbers area (Now Lamaar, Colorado).  This was an audacious move on the part of the traders at Fort Jackson, as it amounted to a direct challenge to the Bent, St. Vrain & Co whose headquarters was at Bent's Fort on the Arkansas River.  

Here is an inventory of goods sent out with the Robertson trading party that has survived (Reference Guy Peterson, 1982).  Here is a comparative analysis of the inventory presented as a paper at the 2015 Fur Trade Symposium in La Junta, Colorado. Other Fort Jackson accounts also show that trade at the fort was not limited to Indian customers, but included numerous mountain men as well.  Surprisingly, Bent, St. Vrain, & Co; Lupton, L.P.; and Vasques [sic] & Sublette show up on these accounts as well. 

The 1838 negotiations between the American Fur Company and Bent, St. Vrain & Co. produced an agreement between the two companies regarding trade in the area.  The American Fur Company would not send trading parties south of the South Platte river, while Bent & St. Vrain Company would stay clear of the North Platte River.  As part of the agreement, the entire inventory of goods, supplies, and tools at Fort Jackson was to be sold to Bent, St. Vrain & Co.  Able Baker, Jr. was the factor at Fort Jackson at this time and when Henry Fraeb left Baker in charge of the fort he left a detailed set of instructions to be followed in his absence.  It is reported that Baker was totally unaware that the sale of Fort Jackson was in the works until William Bent arrived to take possession of the fort.  

On October 6, 1838, the contents of Fort Jackson were removed to Fort George. Shortly thereafter, a party was sent down from Fort Laramie (Fort William) with the purpose of destroying Fort Jackson.  The destruction met with no objection from the proprietors of Fort St. Vrain, who probably would have done this themselves to prevent other competitors from occupying the abandoned post.  The destruction of the post was so complete that when F.A. Wislizenus (Reference) passed through the area in 1839 he makes no mention of Fort Jackson.  Here is what he says: "On September 3rd we came quite unexpectedly to the left bank of the South Fork and crossed the river. On the right bank there are here three forts, only some miles apart. Penn's [Bent's] and St. Vrain's fort, Vasquez and Sublett's and Lobdon's [Lupton's] fort."  

There were no contemporary descriptions of Fort Jackson, and even the location of the post is not known except that it was between Fort Lancaster and Fort Vasquez.  That the destruction of the post was so complete that Wislizenus was apparently unaware of its presence a year later suggests that it had not been constructed of adobe as were Forts Lancaster, St. Vrain and Vasquez.  Fort Jackson may have been constructed to serve only as a temporary facility simply to put commercial pressure on the other companies, and may have been intended to be a negotiating sacrifice to Bent, St. Vrain & Co.  As such, it may have consisted only of cottonwood structures.  

For more information about Fort Jackson see:  

Peterson, Guy L:  Four Forts of the South Platte 1982, published by Council on America's Military Past.  

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