This broadside offers a reward for the capture and return of the runaway slave Robert Porter to his master in Maryland. In most of the antebellum era this work remained the work of private bounty hunters who retrieved runaways for such rewards. But the Compromise of 1850, negotiated by Congressional leaders in order to address the growing sectional tensions precipitated by the end of the Mexican War and the question of slavery in the resulting western territories, made catching runaways the duty of every American citizen. The Compromise's Fugitive Slave Act made it a crime for northerners, or any American, to assist or harbor an escaped slave. The Act also provided magistrates with a greater financial reward for judging an apprehended African-American to be an escaped slave than for defending his freedom. Operating in the new legal climate, slave catchers grew bolder, and began kidnapping free blacks and selling them into slavery. While this measure provided some slim comfort to a South increasingly anxious about runaways, it only served to inflame northern opinion against their cause. Where once only dyed-in-the wool abolitionists had spoken out against slavery, now even white men ambivalent about peculiar institution resented the federal government's demand that they become its agents.