Settles on Vermilion River in South Dakota. Chouteau, Jr., navigates first steamboat, the Yellowstone, on upper Missouri, reaching Fort Tecumseh. Revolutionizes fur trade methods. George Catlin, famous painter of Indian pictures, visits Fort Pierre and paints many likenesses. Le Beau arrested by order of William Laidlaw, burgeois of Fort Pierre, and sent to St. Louis in chains.
All tribes suffer severely.
Mandans practically destroyed.