Answer: The major difference between the North and the South -- and the one most responsible for the Civil War -- was the institution of slavery. In the North, slavery was almost universally prohibited by the 1800s, while the institution was a cornerstone of Southern society. In the North, many blacks were free, and in states such as Massachusetts, New York and Ohio, 100 percent of the black population was free. In the states of the Confederacy, by contrast, few blacks were free.
