The university library of Leipzig hosts one of the most extensive and complete early modern collections of hand-written manuscripts of ‘Western learned magic’. The collection was sold in 1710 for an extraordinary price, and both the selling catalogue entitled ‘catalogus rariorum manuscriptorum’ as well as 134 (of 140) manuscripts have survived. The collection is unique in several ways: with numerous texts going back to late antiquity and the Middle Ages, as well as early modern adaptations and innovations, the collection attests both the longue-durée nature of the textual-ritual tradition of ‘Western learned magic’ as well as its striking adaptability and changeability. With over hundred texts translated into German, it attests processes of vernacularising texts and techniques of ‘learned magic’ in German-speaking Europe that happened significantly earlier than assumed thus far. With over 65 % of the texts devoted to the Solomonic art of conjuring spirits, the collection provides a unique window into ritual knowledge that was highly contested and illegal at the time, and at the same time demonstrates that this knowledge was much more elaborate and versatile in the 17th and 18th centuries than assumed thus far. After an introduction into the concept and tradition of ‘Western learned magic’, the lecture provides an overview over the history and contents of the Leipzig Cod. Mag. collection.