Professor Gates finds his genealogical research becoming even more difficult as he continues from the Civil War back through the Colonial period of American history.

Professor Gates finds his genealogical research becoming even more difficult as he continues from the Civil War back through the Colonial period of American history. War service records and records documenting property during slavery's apogee, such as inventories and sales or gifts of slaves, help fill in the participants' family trees. One participant is shocked to learn that an ancestor from this period, though a soldier, was neither African American nor fighting for the Union. Another participant, whose ancestors' slaveholders kept meticulous records, is able to visit the plantation where her ancestors labored; and yet another obtains detailed records thanks to ancestors who were among the few 19th-century southern African Americans who were born and remained free over generations. Historians discuss how large slaveholders would have been bankrupt without free labor, while genealogists explain the difficulties inherent in research when African Americans have spent 12 generations enslaved, and only seven as free people. In West Virginia, Gates learns from a court transcript about the legal struggle of his ancestor Isaac Clifford, a free man who was kidnapped and accused of being a runaway slave.