Jan van Ruusbroec (1293-1381), the most influential medieval Dutch author, is generally acknowledged to be one of the key figures in the tradition of Christian mysticism. This book concentrates on the medieval dimensions of Ruusbroec's authorship. Warnar offers a comprehensive analysis of Ruusbroec's oeuvre within the social, religious and literary frameworks of the fourteenth century Low Countries. Ruusbroec emerges as an author who was fully engaged in contemporary discussions on the contemplative life and mystical theology, as a charismatic guide who attracted a growing number of disciples first from the Low Countries but soon from all over Western Europe, and as the architect of a vernacular oeuvre of international interest from the Middle Ages to modern times.