Sectionalism eventually led to the American Civil War.
Sectionalism, or regional conflict between the Northern and Southern United States in the early to mid-19th century, was caused by many factors, with slavery, the "Slave Power Conspiracy," economic and cultural differences between the two sections being the primary four factors. Sectionalism competed with nationalism to define American politics during this formative period in American history.
Slavery
The predominant cause of sectionalism was slavery, which, by the early 19th century, had been extinguished in the North. Concurrently, slavery grew stronger in the South with the invention of the cotton gin making cotton farming more viable, and territorial expansion opening up new agricultural lands. Northerners objected to slavery on moral grounds while Southerners began to see slavery as a positive good instead of a necessary evil. They were deeply offended by Northern opposition to slavery, believing that Northerners wanted to ruin the South by banning slavery nationwide.
The "Slave Power Conspiracy"
At the same time, Northerners were deeply offended by the continued existence and territorial expansion of slavery. The idea that Southerners eventually wanted to legalize slavery throughout the whole country took hold in the North: an idea called the "Slave Power Conspiracy." It didn't help that nearly every President of the United States in the early to mid-19th century was either a Southerner or a Southern sympathizer; Southern political skill meant that the South usually dominated Congress.
Economic Differences
The South concentrated more and more on an agricultural slave economy while the North commercialized and industrialized. This led to differences over tariffs and internal improvements. Northerners wanted Northern manufacturing protected with a tariff and federal money spent on aids to commerce, like roads, railroads and canals. Southerners opposed a tariff since it made buying manufactured goods more expensive, and also disliked internal improvements or the higher federal budget necessary to build them.
Cultural Differences
Northern religious attitudes tended to condemn slavery while Southern religious attitudes tended to support it. The Northern tradition of proud, free labor also contributed to an abhorrence of slavery in the North because it was felt that slavery demeaned free labor. The strength of the Southern honor culture also meant that offense at Northern opposition to slavery became a serious issue. Southern fear over potential slave revolts led to uncompromising Southern intolerance of any criticism of slavery, since Southerners believed that criticizing slavery contributed to slave uprisings.
