" The Arabs from Zanzibar convinced them to become Muslim, then recruited them to capture our Chewa people and put us into bondage. They raided our villages, killed our men, then sent our women and children across the lake in boats. Once there, the slaves were shackled by the neck and made to march across Tanzania. This took three months. Once they reached the ocean, most of them were dead. Later on, the Yao captured and traded us to the Portuguese in exchange for guns, gold, and salt. "

― William Kamkwamba , The Boy Who Harnessed the Wind: Creating Currents of Electricity and Hope