Meriwether Lewis ( August 18 , 1774 -- October 11 , 1809 ) was an American explorer , soldier , politician , and public administrator , best known for his role as the leader of the Lewis and Clark Expedition , also known as the Corps of Discovery , with William Clark .
Meriwether Lewis ( August 18 , 1774 -- October 11 , 1809 ) was an American explorer , soldier , and public administrator . He was best known for his role as the leader of the Lewis and Clark Expedition with William Clark .