Ndola is one of the most prominent towns in Zambia's Copperbelt province. Today, the numerous copper mines in the region provide the region's wealth. But in the past, a darker industry spurred the settlement. Still standing near the center of town, the Slave Tree was the central location where Swahili slave traders met to discuss their gruesome transactions. Under its shade, Swahili traders such as Chipembere, Mwalabu, and Chiwala held councils of war and sold enslaved people to the Mambundu from Angola. Much of central and southern Africa, including modern-day Zambia, was crisscrossed by slave traders transporting human captives...