Answer:
Great quarters within the American people soon started questioning slavery altogether after the war since the war itself was motivated by ideals which called for liberty and equality. The evangelical element also played its part as people viewed slavery to be a blatant violation of the Christian belief which said that all Christians had equal rights.
Explanation:
Another reason was the decline in the plantation business, especially tobacco, which caused a drop in slavery. In the north, most states began passing laws soon after the war that abolished slavery.