Arriving in East Africa from South Asia approximately 1000 years ago, cannabis quickly spread throughout the continent. European accounts of cannabis in Africa-often fictionalized and reliant upon racial stereotypes-shaped widespread myths about the plant and were used to depict the continent as a cultural backwater and blacks as predisposed to drug use. These myths continue to influence contemporary thinking about cannabis. In The African Roots of Marijuana Chris S. Duvall corrects common misconceptions while telling an authoritative history of cannabis as it flowed into, throughout, and out of Africa. Duvall shows how preexisting smoking cultures in Africa transformed the plant into a fast-acting and easily dosed drug, and how it later became linked with global capitalism and the slave trade. People often used cannabis to cope with oppressive working conditions under colonialism, as a recreational drug, and in religious and political movements. This expansive look at Africa's importance to the development of human knowledge about marijuana will challenge everything readers thought they knew about one of the world's most ubiquitous plants.