Which factor was the main cause of the Civil War?

The main cause of the Civil War was disputes over slavery and states' rights. This issue was central to the tensions that arose between the Northern and Southern states. The Southern economy relied heavily on agriculture supported by slave labor, while the Northern states were increasingly moving towards industrialization and a wage labor system.

As the nation expanded westward, debates arose concerning whether new states and territories would permit slavery. Southern states wanted to maintain the institution of slavery to preserve their economic interests and way of life, leading to a fundamental conflict with the Northern states, which opposed the expansion of slavery.

Additionally, the concept of states' rights played a significant role. Many Southern states believed that they had the right to govern themselves and make their own decisions regarding slavery without federal intervention. This conflict over the balance of power between state and federal authority escalated tensions and ultimately led to the secession of Southern states and the outbreak of the Civil War.

While territorial expansion, economic challenges, and conflicts with Native American tribes contributed to the overall backdrop of 19th-century America, none of these factors encapsulated the deep-seated ideological and moral conflict that defined the Civil War as accurately as the disputes over slavery and the rights of states to govern themselves.