A divided country
In the early days of the Republic, several states in the North move to abolish slavery while the South, mostly agrarian, holds on to it.
In 1807, the Congress outlaws the importation of slaves.
As the United States expand westward, the balance of power between “slave states” and “free states” is at stake.
“Slaves states” fear that should they become the minority, the “free states” would move to abolish slavery at the federal level.
Abolitionism
It gains traction after the abolition of slavery in the United Kingdom in 1833.
It is motivated by a regain in religious fervor.
Several abolitionist societies formed in the 1830s such as the American Anti-Slavery Society founded by William Lloyd Garrison.
Legal ramifications
The Fugitive Slave Act of 1789 guarantees the return of slaves to their masters even if they are in a free state.
The Missouri compromise of 1820 is supposed to stop the spread of slavery to the new territories in the west.
The Kansas-Nebraska Act of 1854 effectively repealed the Missouri compromise and launched Lincoln’s eventual bid for the presidency.
Dred Scott v. Sandford is a decision by the Supreme court that excludes people of African descent from American citizenship and exclude them from rights and protections guaranteed by the Constitution.