The civil war was caused by slavery wether you agree or not. David Goldfield once said "Both northerners and southerners recognized slavery as the immediate cause of the civil war". The dispute over slavery led to the succession of the south which ignited the war. The southern part of the United States was home to fertile land, on which an agrarian society was established. Slavery was a part of life in the south. It was the reason for the economic success in the south. The northern states were far more technologically advanced. The north had a larger population than the south, they manufactured more goods, and had more railroads, which allowed for easier transport. The north was able to gradually get rid of slavery. Slavery had been interwoven in the culture in the south and without it they would've diminished. The confederates threatened to disconnect from the country if slavery was taken away.
Abraham Lincoln was a key figure during the time period. The republican won the 1860 presidential election, and southerners feared the abolishment of slavery under his power. Lincoln was strongly against the expansion of slavery, although he said he would not interfere with it where it existed.
John Brown, who was another important figure, may also have encouraged the war through his actions in Kansas. The battles started by Brown resulted in the deaths of many pro-slavery settlers in Kansas.
Abolitionists fought to have slavery declared illegal in the territories of the Missouri Compromise. This lead to the supporters of slavery fearing for the abolishment of slavery all throughout the U.S.
The Dred Scott Decision also was an influence for the civil war. Dred Scott was a slave who desired freedom. He requested citizenship through the American legal system, but he was denied, this contradicted the Missouri Compromise, which restricted slavery in certain territories.
Slavery is obviously the theme here, and the war was not caused by anything other than slavery. Some may argue that the war was about agriculture and industry or the protection of states' rights, but this was not the case. All of the above reasons lead to the civil war. These circumstances are common to each other because they are directly related to slavery.