how did African-American artists and composers such as Louis Armstrong, Duke Ellington, Muddy Waters, Scott Joplin and others contribute to a greater sense of national awareness of African-American culture? Why (or why not) are the musical contributions of these artists important regardless of one's ethnic or cultural heritage?

how did African-American artists and composers such as Louis Armstrong, Duke Ellington, Muddy Waters, Scott Joplin and others contribute to a greater sense of national awareness of African-American culture? Why (or why not) are the musical contributions of these artists important regardless of one's ethnic or cultural heritage?