Final answer:
Zell opposed persecuting the Anabaptists and advocated for religious tolerance. The Anabaptists were unpopular for their radical beliefs and practices, including pacifism and separation of church and state, which led to their persecution.
Step-by-step explanation:
Zell, most likely referring to Matthias Zell, a figure in the Reformation, was known to oppose the persecution of the Anabaptists, advocating for religious tolerance. The Anabaptists were unpopular largely because they rejected infant baptism, which was a standard practice of the church at the time, and they called for radical social changes such as the separation of church and state. They were also pacifists, refused to hold public office or serve in armies, and did not accept secular rulers' authority over religious affairs. This made them quite controversial, and many European rulers feared their influence, leading to strong reactions and often violent repression.