The following are the major events that led from the Kansas-Nebraska Act to secession:
* The Lecompton Constitution: In 1857, the pro-slavery forces in Kansas drafted the Lecompton Constitution, which would have allowed slavery in Kansas. The anti-slavery forces rejected the constitution, and the federal government refused to recognize it.
* The Dred Scott decision: In 1857, the Supreme Court ruled in the Dred Scott case that African Americans were not citizens of the United States and could not sue in federal court. The decision further inflamed tensions between the North and the South.
* John Brown's raid on Harpers Ferry: In 1859, the abolitionist John Brown led a raid on the federal arsenal at Harpers Ferry, Virginia. Brown's raid was unsuccessful, but it further increased tensions between the North and the South.
* The election of Abraham Lincoln: In 1860, Abraham Lincoln was elected president of the United States. Lincoln was a member of the Republican Party, which was opposed to the expansion of slavery. The election of Lincoln led to the secession of South Carolina and the other six Southern states.
The Kansas-Nebraska Act was a major factor in the outbreak of the American Civil War. The act reopened the issue of slavery in the territories, and it led to a series of violent clashes between pro- and anti-slavery forces. The act also contributed to the growing tensions between the North and the South, which ultimately led to the Civil War.