In his De Republica Helvetiorum libri duo (1576), Josias Simmler writes that the best form of government is one in which public affairs are managed by a collective entity whose members have sworn to devote themselves to the service of the community. In the 16th-17th centuries, this notion of a good governement was particularly prevalent in cities of the Holy Roman Empire and the Old Swiss Confederacy. My project looks at the repercussions of this political ethos on municipal iconography in four cities that adopted the Reformation at the beginning of the 16th century (Nuremberg, Ulm, Bern and Zurich). It analyses the ways in which this ideal of good government was staged by actors needing to establish the legitimacy of their political model, justify their choice of religion and resist the appetites of neighbouring powers.