Why did the Civil War begin?

One of the biggest arguments between the north and the south, was whether or not the new states (California, and other states in the west) would be a slave state or a free state. Who ever gained those states would get the advantage to stop slavery from spreading. When the north won California and another state i believe, the south felt cheated and wanted to secede then but the compromise of the fugitive slave law was issued keeping them in the union.

Southern slave owners could see that eventually Congress was likely to outlaw slavery.

There were also states' rights issues. The South had resented tariffs that were imposed to protect Northern industry at the expense of the South who had to pay for imports .