Just as the Civil Rights Era was bubbling, Harry Belafonte released "Day O!" (1956), a Jamaican folk song about a worker getting his just due after a long night on the graveyard shift. This and many other songs symbolically or explicitly spurred the civil rights movement, as spirituals did to help guide slaves to freedom through the Underground Railroad, and as Jay Z says that hip hop does to inspire folks out of poverty ("Do this s--t for my town/Leave the door open hoping they kick it down," he spits on "Nickles and Dimes"). But no matter how music evolves, it's important that we remember. Click on for more songs that we need to keep playing.