Forbidden Books and Royal Horoscopes: the Practice and Censorship of Astrology in Early Modern Portugal

Abstract In sixteenth-century Lisbon, Aires Vaz and Manuel Rodrigues were summoned to the Inquisition on account of their astrological practices. Records of the trial of Vaz and Rodrigues provide valuable information regarding the training and practice of an astrologer in sixteenth-century Portugal. Prior to this study, however, our knowledge on these matters was scarce and mostly indirect. In this article, we argue that the study of these trial records is crucial to understanding both the practice and the regulation of astrology. Studies on the censorship of astrology usually emphasize the importance of the Roman Index, the Tridentine Rules, and the papal bulls against astrology. By looking at these two trials, this article sheds new light on the application of the Roman rules and allows us to trace the general profile of an astrologer in early modern Portugal.