Slavery is one reason why the Civil War was started. The reason why Slavery led to the Civil War is because there were many fights and breakouts over the places Slavery can and can not be because one half of the states wanted it and the other half did not. The South also threw many attacks at the North including Bleeding Kansas and Harper's Ferry. This is one reason that the Civil war was started.
Another reason why the Civil War was started is Harper's Ferry. This is included as a reason why the Civil War