In what ways did Slavery play a major part previous to the civil war, during the civil war, and after the civil war.

It was the main reason

Explanation:

The main reason of the Civil war was because of the North's and South's disagreement on slavery. Previous to the civil war, the North didn't rely on slavery as much as the South did becase it was more industrial. The South relied almost purely on agriculture, so their needed free labor to make it work. During the civil war, enslaved people faught for their freedom, along with others. After the Civil war, the South's economy took a big dip because it was harder to grow crops. The North and South disliked each other bc of it, but it worked eventually.

from the conditions of the working class in england by friedrich engels,the main idea is :

im going to go with b.