Again, not accurate.
Slaves who fought for the Confederacy, and there were thousands of them, were freed and compensated the same as any other soldier. Most were also granted land. Many joined up to protect the territory they loved.
I will not deny that some plantation owners mistreated their slaves, just as some northerners mistreated theirs. But ask yourself this question: You are a Southern plantation owner. You have a large farm, crops, livestock, barns, machinery, all the stuff that goes with it. It all costs money. You have bought slaves to work this land. Would you beat them? Why throw your money away? It would be similar to beating your horses to death in your mind. It made no sense.
So while slave conditions were far from ideal, they were also not routinely mistreated. The overwhelming majority of slave owners valued their slaves, and had no interest in mistreating them as we commonly define the term. These slaves, in turn, often felt a sense of loyalty to their owners. Not like family by any means, but a lot of them considered the treatment they got here better than what they left in Africa when their very tribal leaders sold them as slaves in the first place. They felt betrayed by their own folk, and many had no desire to leave the South. All they wanted was the freedom to own their own farms and raise their own crops and the other priviledges their owners enjoyed. So when they got a chance to do that by joining the Confederate army, a lot of them took it. And according to this Union soldier's letter, it was the wise choice it appears.
I say it again...there was no moral high ground claim for the Union army. Their actions were unspeakably evil. They invaded. They raped. They murdered civilians. They stole, looted, burned, and pillaged. They inflicted this on a group of people who did not attack them, did not try to overtake them, who offered them peaceful relations nationally, who made concessions for the release from a voluntary pact. Put the events in a contemporary context, and 90% of Americans would support the Confederacy.
Any foreign nation that fights for liberation and freedom, we back them. Except when some of our own people wanted it...then it was wrong.
Hypocrites.