The North Platte river was the dividing line, in the days of the trappers, although the Sioux were sometimes found south of the line. _i3/2386
In 1850 the scourge of cholera swept along the trail, and spread among the Indians east of and around Scotts Bluff, and its vital effect drove all else out of mind for a time. Stansbury found five lodges full of Sioux, all dead of cholera, at Ash Hollow, and cholera was raging in a village of two hundred and fifty lodges farther up the Platte.
The Sioux at that time seemed to have practically the undisputed possession of the Platte except the challenge of authority thereover made by white people along the Great White Medicine Road. The river for a time had been the dividing line between the Sioux and the southern tribes, but the southern resistance to the northern pressure was gradually giving way, and soon after the Sioux took possession of the land south to the "South River" and some distance beyond.
Samuel Parker, the missionary, when passing through the North River land in the early thirties, tells of a thousand Pawnees in a village in Mitchell valley, and from 1845 to 1855 the Indians held their pow-wows in Horse creek where Crows and Snakes met the Arapahoes, Cheyennes and Sioux, and presents were distributed among them. This was in line with the promises of Colonel Kearney at Fort Laramie in 1845, where he warned twelve hundred Sioux that they must not try to close the Great White Medicine Road, "for it was used by the people who with their wives and their children and the cattle, were moving to the other side of the mountains, to bury their bones there, and to never return." Colonel Kearney said in address : "Sioux, you have enemies about you. but the greatest of them all is whiskey.