"Strange Fruit". Written by Abel Meeropol, sung by Billie Holiday.
Bob Dylan wrote a lot, among them "The Lonesome Death Of Hattie Carroll", "Oxford Town", "Hurricane", and "The Death Of Emmitt Till".
All the above are related to the lingering (to this day) racism in The United States Of America, following the end of slavery, our original sin. And all are stories about African-Americans murdered (with the exception of "Hurricane") at the hands of white Americans.
A great related movie is To Kill A Mockingbird, a film I first saw as a child. It had a profound effect on me, and remains a favorite of mine.