According to my g-grandfather, some of ours fought for the North. I have a picture of the grave site of one that was a Union officer. The ancestors that fought for the South only did so because Union armies attacked them. He said that they were dirt poor and all they had were their farms. After the Union armies attacked them, burned their crops, stole their livestock, and tried to starve them, they decided to fight. If it had been the Confederate army attacking them, they would have fought for the Union. With them, it was only about surviving and self-defense. They were not going to sit back and let all they had be destroyed.
My g-grandfather was born in 1865 and grew up in the years after the war. He died in 1962 when I was in grade school. He told me stories about growing up on the farm after the war and working side-by-side with free black sharecroppers. He said they were all poor. They were all hated. He said that if they and the black sharecroppers hadn’t teamed up, they would have all starved.
There were a lot of reasons that our ancestors fought for the side they fought for, including the reasons yours did. Most didn’t fight to preserve slavery. Slavery was the rich person’s game.
I will take his word any day over today’s revised history.