Yitzchak ben Moshe of Vienna יצחק בן משה מווינה
(c.1180 - c.1250 CE) (1180 - 1250 לספירה בקירוב)
Born in central Europe, his studies took him west to the great Torah luminaries of the day in France. When he returned, he brought their Tosafist approach back to central Europe, first to Wurzburg and then to Vienna. He is most famous for his legal tract, Ohr Zarua. Among his students was Maharam of Rothenburg.