Answer:
Prior to the start of the Civil War, there were wide structural differences between the northern and southern United States.
Thus, in economic terms, the north was an industrialized region, with an incipient manufacturing and ship production as the main economic base of the region, in addition to being the main point of trade for the country. Furthermore, the development of the Erie Canal allowed for greater diversification, dividing production between the Midwest, New England, and major cities such as New York and Philadelphia.
For its part, the south was a much less industrialized region, which based its economy on agricultural and livestock production, especially on cotton, tobacco and various grain plantations, which meant that its economy did not have the diversity that would allow it to develop economically.
In demographic and social terms, the two regions were also very different. Thus, the north had more than twice as many inhabitants as the south, and it was a much more liberal society, which respected the rights of its inhabitants and was against slave labor. Instead, the south was a much more conservative region, where its inhabitants relied on religious precepts more strictly, and where slavery was considered a legitimate means of economic production.
