On May 24, 1856, John Brown, self-appointed avenger, four of his sons and two other followers, raided a settlement on the Pottawatomie Creek in Franklin County, Kansas dragging five innocent proslavery men from their homes, they hacked them to death with artillery swords. After Osawatomie, John Brown earned the nickname "Osawatomie Brown" as he led anti-slavery guerrillas in the fight for a free Kansas during the rest of the year.

In retaliation, the town of Osawatomie was attacked by 400 pro-slavery Missourians in August, 1856. John Brown, along with forty other men defended the town, but in the end, all but four homes at the settlement were burned by the invaders and John Brown's son Frederick was killed. Four wagon loads of dead and wounded were brought into Booneville, Missouri when the invading army returned.

In September of 1856, a new territorial governor, John W. Geary, arrived in Kansas and began to restore order.   However, his tenure was to be a short one as, when, in 1857, the Lecompton legislature met, it became clear that free elections would not be held to approve a new constitution and Geary resigned. Robert J. Walker was then appointed governor, and a convention was held at Lecompton where a constitution was drafted. Only that part of the resulting pro-slavery constitution dealing with slavery was submitted to the electorate, and the question was drafted to favor the pro-slavery group. Free-state men refused to participate in the election with the result that the constitution was overwhelmingly approved.

1857 was also the year that saw William Clarke Quantrill’s arrival upon the scene. The former Ohio school teacher moved to Kansas and took up farming for a time. However, he quickly honed his violent nature by living with thieves and murderers, committing several brutal murders during this time. The next year he would rode West with a wagon train, supporting himself through gambling. Later he would return, taking an active part in the bloody battle between Kansas and Missouri.

Despite the dubious validity of the Lecompton constitution, President James Buchanan recommended, in 1858, that Congress accept it and approve statehood for the territory. Instead, Congress returned it for another territorial vote, moving the nation closer to war.