Border Ruffian The Border Ruffians were pro - slavery activists from the slave state of Missouri , who in 1854 to 1860 crossed the state border into Kansas Territory , to force the acceptance of slavery there . The name was applied by Free - State settlers in Kansas and abolitionists throughout the North . Armed Ruffians interfered in territorial elections , and attacked Free - State settlements . This violence was the origin of the phrase " Bleeding Kansas " . The Ruffians contributed to the growing sectional tensions , and helped bring on the American Civil War . Notably , only a few of the Border Ruffians actually owned slaves ; most were too poor . What motivated them was hatred of Yankees and abolitionists , and fear of free blacks living nearby . The Ruffians were driven by the rhetoric of leaders such as U . S . Senator David Rice Atchison of Missouri , who called Northerners " negro thieves " and " abolitionist tyrants . " He encouraged Missourians to defend their institution " with the bayonet and with blood " and , if necessary , " to kill every God - damned abolitionist in the district . " Ironically , the bulk of Free - State men in Kansas were not abolitionists , and opposed the presence of both free blacks and slaves . " We want no slaves and we want no Negroes " was the prevailing sentiment reported by an abolitionist in 1854 . Additionally , the presence of bands of both Kansan and Missourian combatants in the area made it difficult for families on the border to remain neutral . The Border Ruffians in " Bleeding Kansas " . Kansas Territory was created by the Kansas - Nebraska Act of 1854 . The Act repealed the previous Federal prohibition on slavery in that area . Instead , the locally elected territorial legislature would decide . At this time , many ( probably most ) of the settlers in Kansas opposed slavery . However , slavery advocates determined to have their way regardless . When elections were held in Kansas Territory , bands of armed Ruffians seized polling places , prevented Free - State men from voting , and cast votes themselves ( illegally , since they were Missourians ) . On 29 November 1854 , Border Ruffians elected a pro - slavery territorial representative to Congress . On 30 March 1855 , the Ruffians elected a pro - slavery legislature . Despite these measures , far more Free - State settlers moved to Kansas than pro - slavery settlers . In 1857 , pro - slavery settlers in Kansas proposed the Lecompton Constitution for the future state of Kansas . The Ruffians tried to get the Lecompton Constitution adopted with additional fraud and violence , but by then there were too many Free - Staters there . The Border Ruffians also engaged in general violence against Free - State settlements . They burned farms and sometimes murdered Free - State men . Most notoriously , the Ruffians twice attacked Lawrence , Kansas , the Free - State capital . On 1 December 1855 , a small army of mainly Border Ruffians laid siege to Lawrence , but were driven off . ( This was the nearly bloodless climax to the " Wakarusa War " . ) On 21 May 1856 , an even larger force of Border Ruffians and pro - slavery Kansans captured Lawrence , which they sacked . ( " See " Sacking of Lawrence ) . Free - State settlers sometimes struck back . Free - State irregulars ( known as Jayhawker s , Redlegs , or Redleggers ) attacked pro - slavery settlers and suspected Ruffian sympathizers . Most notoriously , abolitionist fanatic John Brown killed five pro - slavery men at Osawatomie . The Border Ruffians in the Civil War . During the Civil War , the violence in this area not only continued , but escalated tremendously . Many of the former Ruffians became pro - Confederate guerrillas . They operated in western Missouri , sometimes raiding into Kansas , and Union forces campaigned to suppress them . Farms were burned and looted . Suspected guerrillas were killed ; guerrillas killed Union sympathizers and suspected informers . ( " See " Bushwhacker . ) Many of the Union troops involved were Kansas Jayhawkers , and had deep grudges against Missourians . Jayhawkers destroyed several towns in Missouri , such as Osceola . The destruction of Osceola is depicted in the movie " The Outlaw Josey Wales " .