I'm very familiar with Jack Johnson and his entire story.  He had to chase the Heavyweight Championship for a long time and had to literally chase and harass Burns into giving him his crack at the Title.  He should have been pardoned a long time ago, not sure why it hasn't happened yet to be honest.  Really hope that Trump makes it happen, this is something that is multiple decades over-due.  Johnson's whole story is really fascinating - great post!