Answer:
The abolitionists, people who believed slavery to be immoral and unjust, called for the liberation of all slaves. The Underground Railroad was a code name for the alliance of "safe houses" where escaped slaves could seek refuge along the route to freedom in the North. The South saw abolitionism as a major threat to their way of life. They especially resented that the North granted slaves their freedom in exchange for their fighting on the side of the Union. Many slaves jumped at this opportunity because of the chance to gain their own freedom and to fight for the freedom of others.
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