Josel of Rosheim (alternatively: Joselin, Joselmann, Yoselmann, German: Josel von Rosheim, Hebrew: יוסף בן גרשון מרוסהים Joseph ben Gershon mi-Rosheim, or Joseph ben Gershon Loanz; c. 1480 – March, 1554) was the great advocate ("shtadlan") of the German and Polish Jews during the reigns of the Holy Roman Emperor Maximilian I and Charles V. Maximilian I appointed him as governor of all Jews of Germany, a position which was confirmed after his death by his grandson, Charles V.
His stature among the Jews, and the protected status he gained for himself and for the Jews within the Holy Roman Empire, rested in part on his skills as an advocate and in part from the Jewish role in financing the expenses of the emperor. Josel of Rosheim remains a major figure of the History of Jews in Alsace.
His family probably originated from the French Louhans. One of his ancestors was Jacob ben Jehiel Loans, personal physician to emperor Frederick III, ennobled for his medical achievements, and also Hebrew teacher of the well-known humanist, lawyer and philosopher Johannes Reuchlin.
Despite the favor shown to this ancestor, his family history also shows the precarious position of Jews during this era. In 1470, three of his father's brothers, including Rabbi Elias, were prosecuted in Endingen, brought before the emperor on charges that eight years earlier they had performed a ritual murder at Sukkot.