Three case studies trace the history of urban fraternities in the church state of the 14th and 15th centuries. The central example is Viterbo, a commune on the Via Francigena to the north of Rome, where, after an enthusiastic start, the development of flagellant and other fraternities displayed a more subdued development in the subsequent course of events. The comparison with Orvieto and Assisi, where economic and political conditions were similar but the ecclesiastical background was very different, indicates that the structure of local churches is the main factor determining the history of late medieval fraternities.