1. Slavery: The institution of slavery was the most divisive issue between the North and South. The Northern states had largely abolished slavery by the 1860s, while the Southern economy was heavily dependent on slave labor. The issue of slavery became increasingly contentious as the United States expanded westward and new states were admitted to the Union.
2. States' Rights: The Southern states argued that they had the right to secede from the Union if they felt their interests were not being protected. This view of states' rights clashed with the Northern view of the Union as a perpetual and indivisible entity.
3. Economic Development: The North and South had different economic interests. The North was becoming increasingly industrialized and urbanized, while the South remained primarily agricultural. The South feared that the North's economic dominance would lead to the erosion of its way of life.
4. Political Power: The balance of power between the North and South shifted as the United States grew. The North's population and economic power were increasing, while the South's influence was declining. This led to tensions over representation in Congress, the presidency, and other political institutions.
5. The Election of Abraham Lincoln: The election of Abraham Lincoln as president in 1860 was the final straw for many Southern states. Lincoln was seen as a staunch opponent of slavery and a threat to Southern interests. His victory led to the secession of 11 Southern states and the formation of the Confederate States of America.
The bombardment of Fort Sumter was the first military conflict of the Civil War, but it was the culmination of years of unresolved tensions between the North and South. The war that followed lasted for four years and resulted in the emancipation of slaves, the preservation of the Union, and the end of the Confederacy.