“Things should be as simple as possible but not simpler.”
— Albert Einstein
Your piece, soulful as it is, would have greatly disappointed old Albert. You have taken a complicated subject, the subject of billions of words and counting, and reduced it to black hats versus white. Congratulations. On the plus side, though, you earn many virtue points. You may stop preening now.
I, too, grew up in the South, a child of outsiders, and am much older than you, so was a lot closer to the actual event, and felt its lingering aftermath more keenly. I realized very young that there was more to the story than the simplistic official narrative, delivered loud and clear though every available channel, which ran thus: The South seceded, treasonously, to preserve slavery, and the North selflessly fought to end it. This was a myth, I realized, with approximately the same relationship to the truth as the moonlight-and-magnolias, happy-darkies version the South told itself to cushion the blow of absolute, crushing defeat.
In the penumbra of your narrative, the North was a beacon of freedom, where black people lived happy, productive lives, freed of the curse of prejudice. This is unabashed nonsense, and if you do not understand this then you have no business writing about history. Blacks were deeply resented in the North, and in many ways life was even harder for them there than in the South, where they at least had a place, however tenuous, in the social order. This discord lingers to the present day, in the form of vast slums blighting every large Northern city. I challenge you to find the same in city of the former Confederacy.
There is no value in the oversimplification of history, or in the demonization of an entire people. And by telling only one side, badly, you commit a small act of injustice.