DemocracyNow.org has an excellent video of James Earl Jones reading one of Frederick Douglass’ most famous speeches, The Meaning of July Fourth for the Negro. It was first given on July 5, 1852, in Rochester, New York, in an address to the Rochester Ladies Antislavery Society. Born into slavery, Douglass became a key leader of the abolitionist movie, and one of America’s most gifted writers and orators.

I think you will find Jones’ emotive and iconic voice to be a great fit for such a powerful and eloquent speech. You can read the transcript here. (Unfortunately, I cannot product the video here, so just click the first hyperlink to see if for yourself.)