William Still’s mother, Sidney, and several of his siblings lived in a cottage on the plantation where they were enslaved. Sidney escaped with her children to join her husband in New Jersey, but she was soon recaptured and returned to Maryland. Leaving her two boys behind but taking her two daughters, she fled again, this time successfully. As punishment, her angry owner sold her sons Peter and Levin. Sidney gave birth to her last child, William, in freedom in New Jersey. As an adult living in Philadelphia, William played a critical role as an Underground Railroad agent, helping more than 1,000 freedom seekers in the 1850s. A chance meeting with his long lost brother Peter inspired William to document the experience of freedom seekers who contacted him. In doing so, Still noted the arrival of Harriet Tubman with her three brothers who had escaped slavery on Christmas Day 1854. William Still’s careful records, kept secret until after the Civil War, now help scholars reconstruct details of how the Underground Railroad worked and who was involved.