Note that a date of 1862 would correspond to the Dakota War of 1862, in which the U. S. government cheated the Dakota of Minnesota of their promised benefits, the Dakota fought (led mostly by Little Crow), and the American forces under Henry Sibley defeated the Dakota and forced them west or (in several dozen cases) hung them. If the party that went west followed the Platte (as in the song) rather than the Missouri, they wouldn't have come anywhere near Dakotas who were involved by the conflict, but the other Dakota would likely have been aware of it, and if in fact the party stayed with the Missouri River, they might have encountered hostile Dakota parties.