The Border Ruffians were pro-slavery activists from the US slave state of Missouri who crossed into Kansas to fight against the abolitionist Free Soilers during the Bleeding Kansas violence of 1854-1860. Most Border Ruffians were too poor to afford slaves, but they were driven by the words of the Southern Democrats, who called the northerners "negro thieves" and "abolitionist tyrants". Senator David Rice Atchison encouraged Missourians to defend their institution with bayonet and blood and to kill every abolitionist in Kansas, but the Kansan Free Soilers did not want either free or enslaved African-Americans to be in Missouri; they were united merely by their opposition to the Border Ruffians.