Andreas Karlstadt (also Carlstadt or Karolostadt), Andreas Rudolph Bodenstein (c. 1480-1541), German Protestant reformer, supporter and close friend of Luther. In his 1516 writing, he presented theses denying free will and asserting the doctrine of salvation by grace alone. Karlstandt, who was the leader at Wittenberg during Luther's stay at the Wartburg (from 1521 to 1522), was one of the most extreme of the Wittenberg reformers. Karlstadt denied the Real Presence of Christ at communion and undermined the importance of the church and the sacraments. Upon his return, Luther accused his friend of betrayal and restored the more orthodox practicies. Karlstadt moved to Switzerland, where he became professor of theology at Basel.
