built ten years earlier to compensate loss of Loisel post, and was headquarters of Manuel Lisa during War of 1812-1815.)
1823. General Ashley, lieutenant governor of Missouri, en route to Yellowstone, with cargo of goods and one hundred men, attacked by Rees at Grand River and thirteen men killed and ten severely wounded.
- Colonel Henry Leavenworth, with 220 men, marches from Fort Atkinson, near Omaha, to punish Rees for attack on Atkinson. At Yankton, July 3, Sergeant Samuel Stackpole and six men drowned by overturning of boat. Leavenworth is joined by Joshua Pilcher, manager of Missouri Fur Company, with forty volunteers at Fort Recovery. General Ashley and eighty men join party at Cheyenne River. Seven hundred and fifty Sioux Indians volunteer for the campaign. August 9 Ree towns reached and besieged. Rees punished and beg for terms. First general military movement in Dakota.
1825. General Henry Atkinson and Dr. Benjamin O'Fallon sent up Missouri with an escort of 476 men to make treaties for trade and intercourse with Indian tribes. Very successful. Destroy English influence with Indians. First Fourth of July celebration in Dakota.
- Wamdesapa, a Wakpekuta chief, kills his brother Tasagi and is driven from his tribe. Settles on Vermilion River in South Dakota.
1828. American Fur Company absorbs Columbia Fur Company and becomes dominant in Dakota trade.
1831. Pierre Chouteau, Jr., navigates first steamboat, the Yellowstone, on upper Missouri, reaching Fort Tecumseh. Revolutionizes fur trade methods.
1832. Fort Pierre built to succeed Fort Tecumseh.
- George Catlin, famous painter of Indian pictures, visits Fort Pierre and paints many likenesses.
- Frederick Le Beau, a trader, kills François Querrel, an employee, at mouth of Cherry Creek, on Cheyenne River. Le Beau arrested by order of William Laidlaw, burgeois of Fort Pierre, and sent to St. Louis in chains.
1837. Great smallpox epidemic on Missouri River. All tribes suffer severely. Mandans practically destroyed.
