The Supreme Court Rules, Slaves are property and congress cannot ban slavery from territories.
South Carolina left the union after the Election of 1860 and the other southern states follow, this left the country torn apart or divided. This lead the to Civil War because loyalty was only devoted to certain parts of the country and made the United States weaker and separate.
We are leaving the union!
This act violated the Missouri Compromise by introducing the idea of popular sovereignty. This made the North feel like they could violate the South laws as well. It destroyed a whole party, the Whigs and caused an imbalance in power between the North and South.
Election of 1860
No!! Not him!
When Dred Scott sued his owner for freedom when he was taken into a free state, he was shot down. This pleased the south, but upset the north more as they found it to be unconstitutional. This complicates the case of slavery. This case also disrespected the rules of the Missouri Compromise.
Fugitive Slave Act
Pro-slavery attacked anti-slavery settlements, leading to an even more tense relationship between the north and the south. It lead to an antislavery response led by John Brown. The civil war in the states makes America fear a Civil War. It deepened the disagreement between slavery while murdering and wounding hundreds.
Lincoln won the Election of 1860 with only 40% of the popular votes. This meant 60% had voted for someone else. This could lead to war by disunion and unhappy voters who would not remain loyal.
The local government authorized to seize and return escaped slave to their owners. While this would please the south it would be seen as morally wrong to the north. This caused future problems of the concept of slavery which was a major disagreement between the north and south.