Final answer:
The Southern states seceded from the Union due to the issue of slavery and fear of Lincoln's actions against it.
Step-by-step explanation:
Why did the Southern States decide to secede from the Union?
The Southern states decided to secede from the Union primarily due to the issue of slavery. They believed that the federal government was encroaching upon their rights to own slaves, and they feared that the newly elected President Abraham Lincoln would take actions against slavery. They also felt that secession would preserve their way of life and allow them to maintain control over their economy and political system.
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