In reaction to these threats and to the problem of runaways and the Underground Railroad, a federal Fugitive Slave Law was passed at the initiative of Southern legislators in 1850. The law set a prison term of six months and a two thousand dollar fine for anyone found to be helping a runaway. In addition, the new law authorized federal officials to extradite runaways to their place of origin, no matter how long they had been absent, merely on the word of their owners and without trial.

The Fugitive Slave Law brought a storm of outrage in the North. Abolitionists held meetings and indignant newspaper editors bemoaned the takeover of Congress by Southern interests. In the North, public opinion gradually turned against slavery, often as a matter of regional pride against the combative, presumptuous Southerners, and the battle lines between the North and the South began...