Final answer:
John Brown's Raid was an act of aggression that heightened tensions over slavery, contributing to the hostility between the North and the South.
Step-by-step explanation:
John Brown's Raid was an event that occurred in 1859, when abolitionist John Brown and a group of his followers attacked the federal arsenal at Harpers Ferry, Virginia in an effort to instigate a slave rebellion. This raid added to the hostility between the North and the South because it further heightened tensions over the issue of slavery. Southerners saw the raid as an act of Northern aggression and feared that it was indicative of widespread abolitionist sentiment. This event contributed to the widening divide between the North and the South, ultimately leading to the Civil War.
Learn more about Causes of the Civil War