Answer:
Lewis & Clark's Expedition to the Complex West, available on DocsTeach.org, can be used as an introduction or for a closer study of the Lewis & Clark Expedition. Students will learn that the United States purchased the Louisiana Territory in 1803 and President Thomas Jefferson sent Lewis and Clark to explore west of the Mississippi River in 1804 — though the land was already inhabited and politically complicated. Primary sources demonstrate various political interests, including those of the Spanish, French, British, and several Native American tribes. Students will plot these documents on a historic map of the West.