Fort McKenzie, Montana, was built by Kenneth McKenzie, a Missouri fur trader working for the American Fur Company in 1832. Its objective was to trade with the Blackfoot Indians on the Missouri River near the Mouth of the Marias River.
In 1833, the fort was visited by Alexander Philip Maximilian, Prince of Wied-Neuwied, a noted German scientist and explorer. Staying for several months, he studied the local Indians and collected plant and animal specimens. He was accompanied by Karl Bodmer, an artist who sketched and made paintings of the Indians and scenes in the surrounding countryside.
In 1844, the fort was managed by a fur trader named Francis A. Chardon, who withdrew from the fort when hostilities with the Blackfoot were renewed. He soon established the short-lived post, Fort Chardon, opposite the mouth of the Judith River. This lasted one season when another party was sent from Fort Union, North Dakota, to recover the Blackfoot trade and established a new post about three miles upriver from present-day Fort Benton. The site is located on the Missouri River, six miles above the mouth of the Marias River, near Loma, Montana.