William Clark grew up in Kentucky. Born in 1770, he was the ninth of ten children. He had little schooling. He knew a lot about farming, hunting, and living in the wilderness.

Clark joined the army when he was nineteen. He learned about different Native American tribes. He was a good leader. He had a talent for drawing maps that he would later use on the expedition.

Lewis and Clark met while serving in the army as sharpshooters. They respected each other. They liked one another. Lewis knew he needed a skilled officer to lead the Corps of Discovery with him. He invited his friend, William Clark. Clark quickly agreed. In his reply, Clark wrote, no man lives whith whome I perfur to undertake such a Trip as yourself.

Clark married after the trip. He was a successful businessman. He led the Department of Indian Affairs. He tried to treat the Native Americans fairly. He was a foster father to Sacagawea’s children. He died in 1838.