What event caused Southern states to secede from the Union, just weeks after it happened?

It was the
election of Abraham Lincoln as president which caused the Southern
states to secede. Lincoln was elected president on November on November 6, 1860, and secession
began just a few weeks later: South Carolina went first, on December 20, followed by Mississippi
on January 9, 1861, and then by Florida on the next day.

For the Southern
states, secession from the Union was about saving slavery. They felt that Lincoln wanted to
bring this practice to an end and they were prepared to take extreme action to prevent this from
happening. By the time of Lincoln's inauguration, for instance, seven of the Southern states had
already seceded from the Union and war was just one month away. 

Lincoln's
personal views on slavery were, therefore, one of the most important causes of the Civil
War. 

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