Rabanus Maurus Magnentius, also known as Hrabanus or Rhabanus, was a Frankish Benedictine monk, theologian, poet, encyclopedist and military writer who became archbishop of Mainz in East Francia. He was the author of the encyclopaedia De rerum naturis. He also wrote treatises on education and grammar and commentaries on the Bible. He was one of the most prominent teachers and writers of the Carolingian age, and was called "Praeceptor Germaniae", or "the teacher of Germany". In the most recent edition of the Roman Martyrology, his feast is given as 4 February and he is qualified as a Saint ('sanctus').