The first part of the Acts of the bishops of Cambrai, ordered by Bishop Gerard of Florennes (1012-1051), was written between 1024 and 1025. It belongs to the historiographical genre of the gesta episcoporum illustrated in eighteen western cities between the late eighth and the twelfth century. The Gesta establish a history of the church of Arras and Cambrai, from its beginnings, built around the complete episcopal list, from St Vedastus (c. 500-540) to Erluin (996-1012), Gerard's predecessor: this is the purpose of book I. Before coming to Gerald's episcopate in book III, the author delivers a second original book, devoted to different churches and monasteries, building the sacred space of the diocese. Book III, to which the papers gathered here are devoted, must be read together with the previous two, that set the coordinates, in time and space, of Bishop Gerard, and more generally of the Church of Cambrai in the first half of eleventh century.