Answer: Slavery, use of federal power, etc.
Explanation: Before the Civil War began, the North and South disagreed on many things, but the major dispute between them was the use of slavery. Slavery was what shaped the South's economy, but the North didn't favor enslaved labor. Even after the North tried numerous attempts to end slavery for the whole country, the South still used slaves to work on plantations. It was only then that the Civil War began, which caused the North and South to split. The North became the Union and the South became the Confederacy. Slavery wasn't the only issue that caused them to divide themselves. The South wanted power to the states, and not the Congress, which was another cause for division between the North and South.
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