thumb|Johannes Aventinus<br /><small>illustration from 19th century</small>
Johann Georg Turmair (or Thurmayr) (4 July 1477 – 9 January 1534), known by the pen name Johannes Aventinus (Latin for "John of Abensberg") or Aventin, was a Bavarian Renaissance humanist historian and philologist. He authored the 1523 Annals of Bavaria, a valuable record of the early history of Germany.
Tutor
Having studied at Ingolstadt, Vienna, Cracow and Paris, he returned to Ingolstadt in 1507 and in 1509 was appointed tutor to Louis and Ernest, the two younger brothers of William IV, Duke of Bavaria, all three the sons of Albert the Wise, the late duke of Bavaria. Aventinus retained this position until 1517, wrote a Latin grammar (Rudimenta grammaticae latinae; 1512) and other manuals for the use of his pupils, and in 1515 traveled in Italy with Ernest. In his zeal for learning, he helped found the Sodalitas litteraria Angilostadensis, the "literary brotherhood of Ingolstadt", under the auspices of which several old manuscripts were brought to light; Many of the important authorities that Aventinus collected for this purpose have been preserved only in his copies. He embodied a critical treatment of them in a complete history of Bavaria, Annales Bojorum ("Annals of Bavaria"). His condensed German version, the Bayerische Chronik, is one of the first major works of history written in the German language.