The Paper and the River: Lewis and Clark, the Mandan Villages, and the Making of the American West

Thomas Jefferson drafted the message himself on a January evening in 1803, at a tilted writing desk of his own design: a confidential request to Congress for a modest sum to send a small party of soldiers up the Missouri River. He called the project commercial and scientific. He did not mention that he had wanted the Pacific coast for twenty years, or that no nation living beyond the river would be asked a single question about any of it.

Within months Napoleon had sold the United States all of Louisiana, and in May 1804 Meriwether Lewis and William Clark started upriver. For the next two years and four months their lives rested, again and again, on the people whose country they were crossing. The Teton Sioux confronted them at the Bad River. The Mandan and Hidatsa carried them through a winter at the Knife River villages. Sacagawea's Lemhi Shoshone sold them the horses that took them into the mountains, and after a starving crossing of the Bitterroots the Nez Perce took them in. At the mouth of the Columbia, the Clatsop traded with them through a long, wet winter.

After the trip home across the mountains come the routes the captains passed up, Clark's great map, and what had become of the nations along the river fifty years on. The captains called it discovery. The people who fed them, guided them and sold them horses had known the way all along.