Johannes Trithemius (1 February 1462 – 13 December 1516), born Johann Heidenberg, was a German Benedictine abbot and a polymath active in the German Renaissance, as a lexicographer, chronicler, cryptographer and occultist. He took considerable influence on the development of early modern and modern occultism; among his students were Heinrich Cornelius Agrippa and Paracelsus.