It is impossible to completely understand the history of the medieval church without understanding how bishops' control was exercised in the diocese, and in the city. This book assesses the differences, shifts and changes in the power of the bishop in the cities and the dioceses of Lincoln and Cremona from the middle of the 11th century to the mid-14th century. Lincoln, with the biggest medieval diocese in England and with its unique series of bishops such as Hugh of Wells, Hugh of Avalon, Robert Grosseteste and Oliver Sutton, represents a substantial example to study in order to understand why and how the power of the bishop changed. On the other hand Cremona, with its unique political role during the central medieval centuries and with bishops of the calibre of Oberto and Sicardo, epitomizes the struggle for power and authority the bishops had to face in a communal Italian city. The comparison between the bishop's powers highlights in great detail both the similarities and the differences between the roles and functions of the prelates in the two cities, as indicated by the available evidence and by the questions asked by historians.