Blacks came to signify many factors at the end of the Civil war. Remember, too...there were literally hundreds of little denominations in the South (anyone could declare themselves a ''reverend'' and set up a sect) and not all were very Jesusish. Growing up there, I heard more justifications by "Christians" for slavery/oppression of blacks than you could ever imagine.
Repercussions of that war still echo through the empty minds of many "Christians"...even today.