As hkau said, the lyrics could refer to anyone who "fights the system". But in this case, I believe, also refer specifically to the african american people who struggled to achieve their freedom.
There's specifically some parts in the lyrics like "runaway slave" (quite literal), or "I've been dreaming about my freedom on the underground train" (it could refer to the underground railroad), and other things that make me think this is true.
As hkau said, the lyrics could refer to anyone who "fights the system". But in this case, I believe, also refer specifically to the african american people who struggled to achieve their freedom. There's specifically some parts in the lyrics like "runaway slave" (quite literal), or "I've been dreaming about my freedom on the underground train" (it could refer to the underground railroad), and other things that make me think this is true.