Why did eleven southern states choose to secede after the election of Abraham Lincoln in 1860, and why did Lincoln and the United States go to war in response

The eleven southern states that chose to secede the Union after Lincoln was elected was due to his stand against supporting the franchise of slavery. When the south seceded the Union had no choice but to bring the country back together.

Explanation:

Slavery was the resounding issue but the Union had to make sure the sovereignty of the country remained in tact.

four sitting presidents have been assassinated while in office but the first was abraham lincoln,