Final answer:
Southern states justified their decision to secede from the Federal Union following the election of President Lincoln in 1860 based on their view of states' rights and the protection of slavery.
Step-by-step explanation:
In the years leading up to the Civil War, Southern states justified their decision to secede from the Federal Union following the election of President Lincoln in 1860 based on their view of states' rights and the protection of slavery.
One piece of original documentary evidence can be found in the South Carolina Declaration of Causes of Secession, which stated, 'A geographical line has been drawn across the Union, and all the States north of that line have united in the election of a man to the high office of President of the United States, whose opinions and purposes are hostile to slavery.'
Another document, the Mississippi Declaration of Causes of Secession, argued that the election of Lincoln posed a threat to slavery, stating, 'Our position is thoroughly identified with the institution of slavery — the greatest material interest of the world.'
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