By 1860, Baltimore had a free black population of abou 30,000 people. In contrast, about a tenth of that number of blacks were slaves.
The city was, at once, a place where it was hard to escape from suspicious gate agents like those on steamboats or in train stations, and a place where it was easy to fade into crowds of free blacks, who often were eager to help escaped slaves.
However, even in the company of their masters, slaves had to have "bond" posted for them if they were in parties traveling north across the Mason-Dixon line. That bond could be as high as $500. Once north, runaway slaves could be reclaimed under the Fugitive Slave Law. Only Canada was the answer to this situation.
Baltimore figured in the escape route of many a runaway slave, including the brilliant path to freedom planned and executed about 1835 by William Craft, a Georgia slave, and his extremely light-skinned wife, Ellen, also a slave. William played the part of a slave to a man traveling to Philadelphia for treatment of illness. The man was Ellen, her face bandaged and her arm in a sling to keep her from having to sign papers. She was playing the role of master to her own husband.
The Crafts talked their way north through Charleston and Richmond, and, in Baltimore, through a demand for bond signed by a legal officer. After some delay, they were allowed to proceed with legal papers.
In 1828, Dan Fisher, a Virginia slave of about 20, was sold south to work in South Carolina. He later escaped north, following the railroad tracks into Baltimore and reaching Connecticut with the help of Philadelphia abolitionists.
While the Crafts, Fisher and many others successfully passed through Baltimore, a good number of escaping slaves ended up behind bars here. With its well-developed legal system, Baltimore, apparently, was a sort of depot for imprisoned escapees who had been retrieved from free states on felony charges. This conclusion is based on the frequent appearance of the city name in slave narratives.
Some slaves won their freedom in the courts and others were returned to a life of bondage.
Not all escaped slaves were involuntary guests in the city, however. "When runaway slaves were denied the opportunity to escape across the Mason-Dixon line, they sometimes gravitated toward Baltimore," writes Charles L. Blockson, curator of the Afro-American collection at Temple University.
One historian says that in 1837, nearly 150 runaway blacks were arrested in the city and about the same number were held for not having papers. It stands to reason that the number of slaves living illegally in the city must have been several times the number who were discovered.
Baltimore was a great hide-out town. Among major local "conductors" of the underground railroad were Rabbi David Einhorn and the black freedom worker William Watkins and his family. Baltimore was a major stop, too, for Harriet Tubman on her missions to take escaped slaves north.
Obviously, the Chesapeake Bay, with thousands of miles of shoreline and innumerable navigable creeks, offered a first-class secluded pathway northward, especially from the Eastern Shore into the Philadelphia area. "More fugitive slaves escaped into the north from Maryland than from any other slave state," Charles Blockson says.
For first-hand fugitive-slave accounts, see Charles Blockson's "The Underground Railroad: First Person Narratives of Escapes to Freedom in the North" (Prentiss Hall Press, 1987).