DeWolf descendants looking at family records from the slave trade at the Bristol Historical and Preservation Society, Bristol, RI. (Credit: Holly Fulton) Traces of the Trade: A Story from the Deep North explores the slave-trading background of the DeWolf family of Bristol, Rhode Island. Katrina Browne, who created the documentary, discovered while doing library research that her ancestors had been the largest slave-trading family in U.S. history. The news affected her deeply and she......