Sectionalism, slavery, and states' rights were interconnected causes of the Civil War. Sectionalism refers to the growing divides between the North and South, particularly in terms of economics, politics, and social attitudes. Slavery was a central issue, as the Southern economy relied heavily on slave labor while the North was opposed to the institution. States' rights played a role in the belief that individual states should have the right to govern themselves and make decisions about issues like slavery.
These causes were intertwined as the Southern states felt that their way of life, including the practice of slavery, was being threatened by the increasing power of the federal government. Legislation such as the Fugitive Slave Act and the Kansas-Nebraska Act exacerbated tensions. Popular sentiment in the North against slavery clashed with the Southern defense of the institution. Economic conditions, such as the dependence on cotton in the South, further fueled the divide.
Ultimately, these factors led to the outbreak of the Civil War as the Southern states seceded from the Union in response to Abraham Lincoln's election in 1860. The election results demonstrated the deep-rooted divisions and conflicting ideologies that had been building for decades. The South saw Lincoln's presidency as a threat to their way of life and chose to break away rather than continue within a Union they felt did not represent their interests.