Violence of slavery protests began in Kansas of the 1850's since many settlers began pouring in from both the southern states and northern states. This caused conflict between the pro and anti slavery groups. An example that demonstrates this is the "Sack of Lawrence", a violent attack against a town that was an antislavery foundation. This then set off a series of brutal manslaughter across the states. Just like the "Pottawatomie Massacre" in which John Brown, an American abolitionist, kidnapped five pro slavery men in their sleep and beheaded them for revenge of the "Sack of Lawrence". This cycle of killing went on-and-on leading to the cause of the Civil War.

Littell, McDougal. McDougal Littell the Americans. Evanston, IL: McDougal Littell, 1998. Print.