Write a sentence identifying and describing how one other key event led to the Civil War.

The Peculiar Institution
Slavery arrived in North America along side the Spanish and English colonists of the 17th and 18th centuries, with an estimated 645,000 Africans imported during the more than 250 years the institution was legal. But slavery never existed without controversy. The British colony of Georgia actually banned slavery from 1735 to 1750, although it remained legal in the other 12 colonies. After the American Revolution, northern states one by one passed emancipation laws, and the sectional divide began to open as the South became increasingly committed to slavery. Once called a “necessary evil” by Thomas Jefferson, proponents of slavery increasingly switched their rhetoric to one that described slavery as a benevolent Christian institution that benefited all parties involved: slaves, slave owners, and non-slave holding whites. The number of slaves compared to number of free blacks varied greatly from state to state in the southern states. In 1860, for example, both Virginia and Mississippi had in excess of 400,000 slaves, but the Virginia population also included more than 58,000 free blacks, as opposed to only 773 in Mississippi. In 1860, South Carolina was the only state to have a majority slave population, yet in all southern states slavery served as the foundation for their socioeconomic and political order.