Complex sentence: Michael Stifel or Styfel (Esslingen 1486 or 1487--April 19,1567, Jena) was an Augustinian monk who became an early supporter of Martin Luther and was later appointed professor of mathematics at Jena University.
Split into simpler sentences: Michael Stifel or Styfel (Esslingen 1486 or 1487--April 19,1567, Jena) was a German monk and mathematician. Stifel was later appointed professor of mathematics at Jena University.