Answer:
The victory of Abraham Lincoln in the presidential elections of 1860.
Step-by-step explanation:
The separation of southern states had to do after the presidential elections of 1860 which ended up with the victory of Abraham Lincoln. In the south, the was the fear that Lincoln could remove the institution of slavery, and also, they felt the southern states had to power in the USA. At the end of the first half of 1861, all southern states seceded and formed the Confederate States of America with Jefferson Davis as president.
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