Johannes Trithemius
Johannes Trithemius, born Johann Heidenberg, was a German Benedictine abbot and a polymath who was active in the German Renaissance as a lexicographer, chronicler, cryptographer, and occultist. He is considered the founder of modern cryptography and steganography, as well as the founder of bibliography and literary studies as branches of knowledge. He had considerable influence on the development of early modern and modern occultism. His students included Heinrich Cornelius Agrippa and Paracelsus.