Nathaniel Wyeth was an enthusiast who caught the fever of the wilds; and Captain Benjamin Bonneville a gay adventurer, whose men shot down more Indians in one trip than all the free trappers of America shot in a century. As for the desperado Harvey, his crimes were committed under the walls of the American Fur Company's fort. McLellan and Crooks and John Day -- before they joined the Astorians -- and Daniel Boone Kit Carson and John Colter, are names that stand for the true type of free trapper."

Fights between Whites and Indians

During these years of exploration and trading, while the land yet remained a wilderness wandered over only by little parties of free or employed trappers, the Great Plains and the waters bordering them were the scene of certain events of sufficient historic importance to warrant brief mention. The first recorded fight between Americans and Indians in this region took place in September, 1807, at the Arikara villages on the Missouri River. Here Ensign Pryor of the Army, with fifty men, endeavoring to escort a Mandan chief back to his tribe, was attacked by Arikara on shore, and compelled to retreat after fifteen minutes of hot fighting. The loss of the whites was three killed and ten wounded, one mortally. This point on the river was later the scene of various conflicts, the most serious being the attack on Ashley's men in June, 1823. This battle was fought partly on land and partly on water, and was practically a defeat for the whites, who lost fourteen killed and about as many wounded. It resulted in an army expedition under Colonel Leavenworth being dispatched up the river. A three days' battle was waged in which neither side could claim victory. A treaty of peace was patched up, but the Arikara continued troublesome all through the years of the fur trade.

Earliest Steamboats on the Upper Missouri

In 1826, William Ashley, going West with a party by way of the Platte River, took with him a six-pounder wheeled cannon all the way to Utah Lake. This is believed to be the first wheeled vehicle to cross the Plains north of the Santa Fe Trail. In 1831 the first steamboat to navigate the upper Missouri River. This was the "Yellowstone," Captain Young. It proceeded as far as Fort Tecumseh. The following year this boat succeeded in reaching Fort Union at the mouth of the Yellowstone, and by 1859 steamers had pushed up as far as Fort Benton, near where the Teton River joins the Missouri River..

In 1837 the Indian tribes of the northern Plains were visited by the plague of smallpox. It raged with fearful effect among the Arikara, Mandan, and Assiniboine, spreading westward to the Crow and Blackfoot. The scourge is said to have been introduced by the passage of the annual steamboat of the American Fur Company, the "St. Peters," which had several cases on board. The Mandan suffered most severely, only about thirty remaining alive, and they mostly boys and old men. Chittenden estimates the total loss in the several tribes attacked at more than fifteen thousand, which, considering the probable original population, makes a mortality almost without parallel in the history of plagues. A writer of the time said: "The destroying angel has visited the unfortunate sons of the wilderness with terrors never before known, and has converted the extensive hunting grounds, as well as the peaceful settlements of these tribes, into desolate and boundless cemeteries."