William Clark, born August 1, 1770, in Virginia, was the brother of George Rogers Clark, a hero of the American Revolution. He served in the US Army as an artillery officer. With Meriwether Lewis, Clark led the famous Lewis and Clark Expedition from 1804 to 1806 across the land acquired in the Louisiana Purchase. Clark was a popular leader; he was also popular among the Indians and served as Indian Agent in the Louisiana Territory. He died September 1, 1838.