The alumbrados (Spanish pronunciation: [alumˈbɾaðos], illuminated), also called the illuminati, were the practitioners of a mystical form of Christianity in the Crown of Castile during the 15th–16th centuries. Some alumbrados were only mildly heterodox, but others held views that were clearly heretical, according to the contemporary rulers. Consequently, they were firmly repressed and became some of the early victims of the Spanish Inquisition.