Lewis' Early Life
The initial five chapters of Undaunted Courage explore Lewis' life before embarking on the historic expedition. Born in 1774, Lewis hailed from a prominent plantation family in Virginia. During his childhood, he spent several years living in a frontier colony in Georgia. At thirteen, upon returning from Georgia, he received formal education to prepare him for managing the estate he inherited from his father. However, Lewis only spent a brief period on the Virginia plantation before volunteering for the Virginia militia in 1794. His military service spanned six years and took him across much of the American frontier. In 1801, President Jefferson, a long-time family acquaintance, invited Lewis to serve as his personal secretary and aide. Lewis promptly resigned his military commission and relocated to the president's residence in Washington.

Planning the Expedition
Jefferson had always been keen on organizing an expedition to explore the western territories. His interest intensified upon learning of British plans to engage in the Pacific Northwest fur trade. In 1802, Jefferson appointed Lewis to lead an expedition to the Pacific. Lewis was tasked with three primary objectives: discover an all-water route to the Pacific Ocean, inform Native Americans of their new leadership and integrate them into the American trade network, and investigate the northern tributaries of the Mississippi and Missouri rivers to establish the northern boundary of the Louisiana Purchase. Jefferson was also deeply interested in scientific exploration.

In preparation for the expedition, Lewis immersed himself in studying geography, botany, mineralogy, astronomy, and ethnology with prominent American scientists. He made crucial decisions regarding the supplies needed, the gifts for Native Americans, and the number of men required for the journey. He supervised the construction of a boat to navigate the Mississippi River. Recognizing the need for a co-leader, Lewis selected Clark, whom he had met during his military service. Despite Clark's rank remaining at lieutenant, much to Lewis' disappointment, both men shared command equally. During the preparations, the Louisiana Purchase was finalized, granting the United States ownership of much of the land the expedition would traverse.

Up the Missouri
On August 31, 1803, Lewis embarked down the Ohio River. He rendezvoused with Clark in Clarksville, Indian Territory, where they recruited members for their Corps of Discovery. The team then traveled upriver to Wood River, where they established their winter camp. While Clark managed the trip's preparations, Lewis was responsible for acquiring supplies in St. Louis.

On May 22, 1804, the Corps of Discovery, consisting of nearly fifty men, embarked on their journey. The expedition included a large keelboat and two smaller boats. They traveled over 640 miles upriver before meeting any Native Americans. On August 2, an Oto party arrived at their camp. Lewis informed them about Jefferson, their new Great Father, and presented them with gifts. The expedition faced its only fatality on August 20 when Sgt. Charles Floyd passed away due to a ruptured appendix. In September, they encountered a large group of Sioux and visited their village.

By October, the expedition reached the Mandan villages in what is now North Dakota. The friendly Mandans were central to trade in the Northern Plains. The men constructed Fort Mandan to spend the winter and met a French-Canadian trader named Charbonneau and his wife, Sacagawea, who joined as translators. A small contingent sailed back down the Missouri to report on their progress.

Westward Bound
On April 7, 1805, the expedition prepared to head west. Eight days later, they surpassed the farthest point upstream on the Missouri known to have been reached by white men, according to Lewis. They hunted buffalo and had...