So I've seen a few descriptions and pictures of lynchings and general miss treatment of blacks throughout history.
Yet very little on any organisations or groups that had the specific goal of overthrowing slavers/KKK etc.
Did they exist? If so what sort of successes if any did they achieve?
Just to clarify, would you count John Brown in this group? He was white, so he doesn't meet all your criteria.
Yes, I suppose what I am getting at is today we have "terrorist" organisations in every corner of the globe, fighting what they see as the oppression of land, rights, religion etc.
People are converted to a cause through whatever means, so you have English and Australian citizens fighting in Syria, Americans in Israel etc But I don't think I have ever heard of a "terrorist" type group within the slavery era however there seemed to be sufficient numbers and ways to organise that would have "terrorised" the slavers to such an extent that it made a difference.