One of the main causes of the Civil War was the threat of territorial expansion. By itself, without the presence of slavery, one could reasonably assume there would have been virtually no problems between the North and South involving territorial expansion because as a whole nation, nearly everyone, meaning the white people, wanted more land because the original thirteen states were becoming extremely crowded. This is how the whole concept of Manifest Destiny came about in the early 1800’s, where there was the belief that the United States was destined to expand from the Atlantic to the Pacific Ocean.
One sign of trouble was when Missouri wanted to become a slave state. This raised a heated debate amongst the states. The Missouri Compromise in 1820 eventually allowed Missouri to become a slave state, but Massachusetts was split into a smaller Massachusetts and Maine to keep the balance between the slave and free states. If more land was dedicated to the South, then they would have more power in the Senate because of the slaves counting as three-fifths of a person, giving the South greater representation. Territorial expansion meant a political war of power between the North and the South.
The issue of territorial expansion stems from the issue of slavery. Slavery was arguably at the heart of the differences between the sections, North and South. The South had much to fear if the system of slavery was dismantled. There was the fear of a race war if slaves were freed. Since the vast majority were not treated well, and the fact that they had been enslaved their entire lives, there was the inevitable outcome that the freed slaves would fight back. The slave population at the time generally outnumbered the white population at least two to one in most areas. This was a reasonable fear the white South possessed.
The Civil War ultimately devastated the South, both physically and economically. Although territorial expansion was one of the main causes of the Civil War, it was not the sole main cause. Slavery also played a role in causing tension and eventually catalyzing the Civil War. It can be reasonably assumed that most issues between the North and the South stemmed from slavery. Overall, slavery was the root of the causes of the Civil War, but not the main cause.