In the Kansas territory, a miniature civil war—known as Bleeding Kansas—erupted over the issue of slavery. In May 1856, a proslavery group attacked the free-soil town of Lawrence, stealing and destroying and property. In response to the "sack of Lawrence," radical abolitionist John Brown and his followers assaulted a pro-slavery settlement at Pottawatomie Creek, killing five men. By the end of 1856, nearly 200 Kansans had been killed and property worth $2 million has been damaged or destroyed.

The rivalry in the Kansas territory between pro- and anti-slavery factions resulted in the establishment of two territorial legislatures, each claiming legitimacy.  On December 21, 1857, anti-slavery voters, who constituted the vast majority, boycotted a popular referendum on a proposed slave-state constitution, which therefore passed.  On January 4, 1858, pro-slavery voters likewise boycotted a popular referendum on a proposed free-state constitution, which therefore also passed. 

President James Buchanan, a Northern supporter of slavery, chose to back the pro-slavery constitution, which he sent to Congress for approval on February 2, 1858.  For the next several months, the Lecompton constitution (named for the site of the pro-slavery legislature) was the center of heated controversy on Capitol Hill.  Opposition was led by Senator Douglas, who considered the unrepresentative vote to have been a perversion of his notion of popular sovereignty.

During one late-night session of the House (about 2:00 a.m.), Republican Galusha Grow of Pennsylvania crossed the aisle to the Democratic side to confer with some Northern Democrats.  Democrat Lawrence Keitt of South Carolina yelled at Grow to "go back to your side of the House, you Black Republican puppy!" Grow flung back a derogatory comment about slave drivers.  The two men began scuffling, which caught the attention of their congressional colleagues who joined the fight like two baseball benches emptying for an all-out brawl on the diamond.  One journalist-witness reported that little damage was done because the congressmen suffered "from want of wind and muscle," but Congressman Alexander Stephens of Georgia feared that it could have easily escalated to a serious bloodbath.

This cartoon presents the Grow-Keitt spectacle studiously commented on by two "professor[s] of the noble art of self-defense" (the second, a German American), as if they were analyzing a boxing match.