CROTUS (Rubianus), JOHANN. – German humanist, born at Dornheim (Arnstadt) in Thuringia in 1480; died at Halle in 1539. His real name was Jäger, which is often encountered translated into Latin as Vennator. He studied at the University of Erfurt, where he obtained his bachelor’s degree in 1500.
Having moved to Fulda (1510), he met there Corrado Muth (Mutiums) and Ulrico von Hutten, in collaboration with whom he composed the Epistulae obscurorum virorum (1515). From 1517 to 1520 he resided in Rome and Bologna. Returning to Germany, he was appointed rector of the University of Erfurt, and in that capacity he gave Luther a festive welcome as he travelled to the Diet of Worms (1521), and in a solemn speech exalted him as the man « qui primus post tot saecula ausus fuit gladio sacrae scripturae romanam licentiam jugulare ». But when he later realized that Luther was working not for the good but for the destruction of the Church, he openly declared himself fiercely opposed to the reform movement. Luther therefore heaped insults upon him, calling him an Epicurean and Dr. Kröte (→ toad). Having entered the service of the Elector Albert of Mainz in 1530, the following year he published an apology to defend him against the attacks of the Lutheran Alessio Krosner: Apologia, qua respondentur temeritati calumniatorum non verentium conficiis criminalibus in populare odium protrahere Reverendissimum in Christo patrem et dominum Albertum... a Joanne Croto Rubeano privatim ad quendam amicum conscripta (Halle 1531). The Archbishop of Mainz, as a token of gratitude, appointed him a canon of Halle.