Francis Scott Key ( August 1 , 1779 - January 11 , 1843 ) was an American lawyer and poet . He is best known for writing the `` The Star-Spangled Banner '' , which is the national anthem of the United States of America . Francis Scott Key ( August 1 , 1779 â `` January 11 , 1843 ) was an American lawyer , author , and amateur poet , from Georgetown , who wrote the lyrics to the United States ' national anthem , `` The Star-Spangled Banner '' .