"Noel Brann has chosen a controversial and little understood historical figure as the focus of this book. Although Trithemius has been treated before in biographical studies, this is the first exhaustive treatment of Trithemius's magical theology, the most elusive and most provocative aspect of his contributions. Brann's presentation is cautious, original, and persuasive. He strikes out into areas that have not been treated before. Brann is able to interpret Trithemius by revealing the background of his views, by reconstructing their contexts, and by tracing their impact." — Frank Baron, University of Kansas