Slavery created unfair economic competition for Northern white workers. Southern workers were paid less because enslaved workers were not paid at all. This disparity in wages drove down wages for all workers, including Northern whites, and threatened their economic security.
Moral and Religious Opposition
Anti-slavery sentiment in the North was also fueled by moral and religious objections to slavery. Many Northerners viewed slavery as a violation of human rights, with religious groups taking a leading role in the abolitionist movement. Quakers and other religious denominations saw the inherent inequality and cruelty of slavery as inconsistent with their beliefs, leading to a moral condemnation of the practice.
Political Power Dynamics
The political divide between the North and South also contributed to opposition to slavery. As more and more Western territories became states, the issue of whether they would allow slavery became increasingly contentious. The North, with a growing population and expanding economy, desired more free states to increase its political influence. The South, relying heavily on slavery for its economic prosperity, sought to preserve the institution by ensuring the addition of new slave states. This conflict over the balance of power between free and slave states further intensified Northern opposition to slavery.