Slavery in the United States
Main article: Slavery in the United States
Although the trans-Atlantic slave trade ended shortly after the American Revolution, slavery remained a central economic institution in the Southern states. All the Northern states passed emancipation acts between 1780 and 1804; most of these arranged for gradual emancipation.[108] In the South, however, slavery expanded with the westward movement of population. Historian Peter Kolchin wrote, "By breaking up existing families and forcing slaves to relocate far from everyone and everything they knew" this migration "replicated (if on a reduced level) many of [the] horrors" of the Atlantic slave trade.[109] Historian Ira Berlin called this forced migration the Second Middle Passage. Characterizing it as the "central event in the life of a slave between the American Revolution and the Civil War, Berlin wrote that whether they were uprooted themselves or simply lived in fear that they or their families would be involuntarily moved, "the massive deportation traumatized black people, both slave and free."[110] By 1860, 500,000 slaves had grown to 4 million. As long as slavery expanded, it remained profitable and powerful and was unlikely to disappear. Antislavery forces, however, proposed to put it on the path to extinction by stopping further expansion. If it became unprofitable, few people would spend the large sums of cash needed to buy and keep slaves, and the system would fade away quietly as it had in most countries in world history.
The plantation system, based on tobacco growing in Virginia, North Carolina, and Kentucky, and rice in South Carolina, expanded into lush new cotton lands in Georgia, Alabama, Mississippiand needed more slaves. But slave importation became illegal in 1808. Although complete statistics are lacking, it is estimated that 1,000,000 slaves moved west from the Old South between 1790 and 1860. Most of the slaves were moved from Maryland, Virginia, and the Carolinas. Michael Tadman, in a 1989 book Speculators and Slaves: Masters, Traders, and Slaves in the Old South, indicates that 6070% of interregional migrations were the result of the sale of slaves. In 1820 a child in the Upper South had a 30% chance to be sold south by 1860.[111]
Political division over slavery was temporarily resolved by the Compromise of 1850 which sought to divide new territories between slave and free states. However, the status of Kansas was left unresolved, producing bloody clashes between pro-slavery and anti-slavery settlers.[112] In 1860, the election of Abraham Lincoln as President on a program of limiting slavery led to the secession of Southern States and the outbreak of the US Civil War. Although Lincoln initially disclaimed any intention to interfere with slavery, the progress of the war produced the Emancipation Proclamation freeing slaves in Southern states still in revolt, and ultimately the Thirteenth Amendment to the United States Constitution in December 1865, which ended legalized slavery in the United States.