In the seventeenth century, tobacco was fiercely debated from England to Istanbul. Muslim scholars from Bornu and Baghirmi participated in this debate and maintained that smoking was forbidden by divine law, long after their counterparts in the heartlands of Islam allowed it. The question addressed here is why and how the adamant rejection of tobacco in central sudanic Africa was formulated. The study is based on a number of Arabic manuscripts from the region and focuses on a treatise, written around 1700, by Muḥammad al-Wālī b. Sulaymān. It is argued that he was as much inspired by the popular opinion about tobacco in his home-environment as by the writings of scholars from the Middle East. In folktales, tobacco was literally demonised, and the rejection of “pagan” smokers helped to mark new social boundaries. The dominant position regarding smoking was the result of an exchange between islamic learning and popular culture in the region.