William Still is one of the most important figures in the history of the Underground Railroad’s Philadelphia operations. He was born free in New Jersey in 1821, the youngest child of a formerly enslaved couple. He moved to Philadelphia in 1844 and joined the Pennsylvania Anti-Slavery Society, eventually serving as chairman of its Vigilance Committee — the body responsible for receiving and relocating freedom seekers who arrived in the city.
Still kept meticulous records of the people he helped, at considerable personal risk. After the Civil War, he published those records as The Underground Railroad (1872), a comprehensive history of the network based on his own documentation. Brown’s escape appears in that history, verified by Still’s direct participation. Still was the son of a freedom seeker himself; his mother had escaped from Maryland, leaving two children behind, a biographical fact that gives his commitment to the work a personal dimension beyond ideology.
James Miller McKim was a white abolitionist from Pennsylvania, a leading figure in the state’s antislavery society and a gifted organizer. He was one of the people who had been contacted by Samuel Smith before the escape to confirm that there would be someone at the Philadelphia end to receive the box.
Passmore Williamson was a Quaker merchant whose address served as the box’s destination. He was himself no stranger to legal risk in service of the antislavery cause — he was imprisoned for contempt of court in 1855 in connection with another freedom seeker case, an incident that drew national attention.