Editing Louisiana Purchase (section)

==Asserting U.S. possession==
[[File:Fort Madison 1810.jpg|thumb|upright|Plan of [[Fort Madison]], built in 1808 to establish U.S. control over the northern part of the Louisiana Purchase, drawn 1810]]

After the early explorations, the U.S. government sought to establish control of the region, since trade along the Mississippi and Missouri rivers was still dominated by British and French traders from Canada and allied Indians, especially the [[Sauk people|Sauk]] and [[Meskwaki|Fox]]. The U.S. adapted the former Spanish facility at [[Fort Belle Fontaine|Fort Bellefontaine]] as a fur trading post near St. Louis in 1804 for business with the Sauk and Fox.{{sfnp|Luttig|1920|p={{page needed|date= February 2015}}}} In 1808, two military forts with trading factories were built, [[Fort Osage]] along the Missouri River in western present-day Missouri and [[Fort Madison, Iowa|Fort Madison]] along the [[Upper Mississippi River]] in eastern present-day Iowa.{{sfnp|Prucha|1969|pp=99–100}} With tensions increasing with Great Britain, in 1809 Fort Bellefontaine was converted to a U.S. military fort and was used for that purpose until 1826.<ref>Browman, David L (2018). Cantonment Belle Fontaine 805–1826 The First U.S. Fort West of the Mississippi River. Washington University in St. Louis Press. pp. 4 and 7.</ref>

During the [[War of 1812]], aided by their Indian allies, the British defeated U.S. forces in the Upper Mississippi; the U.S. abandoned Forts Osage and Madison, as well as several other U.S. forts built during the war, including [[Fort Johnson]] and [[Fort Shelby (Wisconsin)|Fort Shelby]]. U.S. ownership of the whole Louisiana Purchase region was confirmed in the [[Treaty of Ghent]] (ratified in February 1815).<ref>James A. Carr, "The Battle of New Orleans and the Treaty of Ghent." ''Diplomatic History'' 3.3 (1979): 273-282 doi.org/10.1111/j.1467-7709.1979.tb00315.x.</ref> The U.S. later built or expanded forts along the Mississippi and Missouri rivers, including adding to Fort Bellefontaine, and constructing [[Fort Armstrong (Illinois)|Fort Armstrong]] (1816) and [[Warsaw, Illinois|Fort Edwards]] (1816) in Illinois, [[Fort Crawford]] (1816) in Wisconsin, [[Fort Snelling]] (1819) in Minnesota, and [[Fort Atkinson (Nebraska)|Fort Atkinson]] (1819) in Nebraska.{{sfnp|Prucha|1969|p={{page needed|date= February 2015}}}}