Welcome to History 101. America was like every other nation in the world at its founding... there was slavery. Blacks owned slaves in the South, as did many Whites... BUT, the VAST majority of Whites did not own a single slave. The Civil War began because the North was determined to impose its will on the South.
Gosh, do I believe slavery is wrong? Yes. Thanks for assuming that it’s 2017.
FIFY
You didn’t answer the question. The battle cry was “freedom”. Freedom for who?
Yes, the Civil War began because the North was determined to impose its will on the South. And one of the things it wished to impose was that you can’t own human beings. But you go ahead and keep thinking that slavery had nothing to do with it....