sentences:  Johann Wilhelm was a member of the House of Wettin, which had served as the protecting power of Protestantism in Germany since the time of Frederick the Wise, yet he allied himself with the Catholic King of France against the Protestants Huguenots.The Emperor played off the two surviving sons of Johann Friedrich II against Johann Wilhelm, and in 1572 the Division of Erfurt was concluded.The duchy of Saxony was divided into three parts.