The plague, abuses in the church, and mysticism constitute the background for considering forerunners of the Reformation. They should not be viewed as directly causing the Reformation, but as anticipating in various ways reformational concerns. While some advocated practical reforms (e.g., Jan Hus and Savonarola), others developed theological reflection (e.g., the Brethren of the Common Life). Conciliarism, another reform movement through councils, ironically by its failure, propelled the cause of the Reformation. Finally, humanism, by its return to the sources and Scripture, paved the way as well. In conclusion, it is observed that the division between forerunners and Reformers sometimes is not very definite.