What were the principle causes of the Civil War?

The American Civil War occurred as a result of conflicting views with regards to slavery. The Southern states forming the Confederate States of America were in support of slavery because they relied on the brutal practice to provide labor to run their farms and homes. On the other hand, the North, as the Union, was against slavery. Initially, some of the Northerners believed that slavery should not be allowed to spread, and eventually, sustained pressure from the South forced them to take measures to abolish the practice altogether.
Seven Southern states seceded after President Abraham Lincoln assumed control of the executive branch. Tensions flared, and Confederate soldiers attacked Fort Sumter. Confederates' push against Lincoln was based on the knowledge that Lincoln was anti-slavery. As president, Lincoln was forced to respond with violence to address antagonism by the Confederates in the South.
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