Renowned for his protest songs, Seeger was blacklisted by the US Government in the 1950s for his leftist stance.
Denied broadcast exposure, Seeger toured US college campuses spreading his music and ethos, later calling this the “most important job of my career”.
He was quizzed by the Un-American Activities Committee in 1955 over whether he had sung for Communists, replying that he “greatly resented” the implication that his work made him any less American.
Seeger was charged with contempt of Congress, but the sentence was overturned on appeal.
and a lovely tribute from Ev here