John Brown's raid impacted the national issue of slavery by helping towards the civil war. He and his sons fought against slavery by killing the pro-slavery farmers with a broadsword. This fight was known as "Bleeding Kansas". It ended up erupting into a low-scale civil war, which no doubt, advanced the cause of the full-blown Civil War between the North and the South. Pro-Slavery settlers and anti-slavery settlers both settled in Kansas at the same time. So it was inevitable that the two sides would clash.