A group of writings from 9th-century Le Mans (France) documents this episcopal city in the early Middle Ages. The main contents are an episcopal history (Actus pontificum) and a biography of the last bishop (Gesta Aldrici). These histories contain 84 private and royal charters of which as many as half are partly or wholly inauthentic (‘forgeries’). Nevertheless, the ensemble constitutes the richest of the French episcopal histories. Notably, the Actus contains the extraordinary, genuine Merovingian testament of Bishop Bertrand (616). Many scholars, attracted by the problems of spuriousness, have pored over these writings, tested the charters, and determined their goals. They have also shown that the collection dates to 855–862. A new approach has been made to exploiting the corpus as a valuable source for local history.