The dense forests of the East gave way to plains and deserts west of the Mississippi River. Even the pine stands on western slopes were less thicketed beneath their boughs and more easily traveled. Indian fighters establishing trails in the West, however, had to spend more time finding passes through snow-capped peaks and linking water holes in the arid country. But, the western Indian fighters with their "cousins" in the East had one significant challenge in common: Both groups found a peaceful, gift-bearing approach worked best at times and fighting became unavoidable at others. In one important incident, a blustery but successful bluff allowed for the ultimate success of the greatest pathfinding expedition in American history.

A Tense Beginning

A mounted party of Indians, Teton Sioux, appeared on the bank of the upper Missouri River in September of 1804 and indicated...