I’m not sure if this helps but, after the Kansas Nebraska Act passed, a stricter slave law was placed which resulted in the North becoming angrier. There was also the book by Harriet Beecher Stowe, it was Uncle Tom’s Cabin which was a book wrote to expose the horrors or truths of slavery. This angered the South and led to many Northerners to becoming abolitionists. I’m not sure if this helps.
