Recent scholarly writings on the rôle of coinage in Carolingian commerce have focused upon two recurrent problems: first, upon defining the function of coin as money in the Carolingian economy, and second, upon determining the commercial relations of the Carolingian empire with other peoples, especially with Islam and Byzantium. Logically, numismatic remains ought to be critical in solving these problems; but, in practice, knowledge of them is so imperfect that scholars cite the same numismatic evidence in support of different and sometimes quite contradictory theses. This confusion exists, in part, because there is no comprehensive analysis of the relevant literary and numismatic remains from which sound conclusions in monetary history may be drawn: there is no systematic compendium of Carolingian numismatics. Rather, two primary nineteenth-century catalogues must be consulted in classifying mintage: that of Prou, which describes the Carolingian collection in the Bibliothèque Nationale, and that of Gariel, which inventories Gariel's private collection (the major part of which is now in the Staatliche Museen zu Berlin) with some incidental reference to the cabinets of the Bibliothèque Nationale, the Bibliothèque Royale in Brussels, the civic museums of Marseilles and Rheims, and two private collections other than Gariel's. These two works together list approximately 2,500 of the estimated 5,000–8,000 extant Carolingian coins. Yet no work attempts to harmonize the discrete classifications of Prou and Gariel or to record the approximate number of pieces surviving from the production of each Carolingian mint by inventorying major collections other than those in Paris and Berlin and by collating this data with reports of coin finds in specialist journals. Consequently, it is difficult to gain any clear or accurate knowledge of the importance official coinage assumed in commerce between the eighth and the late tenth century. Research towards a corpus of Carolingian coins undertaken in recent years, however, makes it possible to define the numismatic evidence now more precisely than before and to assess its meaning for economic history more exactly.

By their exchange of articles in the Studi Gregoriani, M. Fliche and the Canon Arquillière have reopened the question of what actually happened when Pope Gregory VII received Henry IV at Canossa. Both scholars assume that Henry approached the Pope, excommunicate and stripped of the royal office; but they differ widely in interpreting Gregory's reception of the penitent King. Taking issue with views Arquillière had expressed in his work Saint-Grégoire VII, Fliche maintained that when Gregory released Henry from excommunication he also reinstated him in the royal office. In response, Arquillière reaffirmed his earlier position that only the ban, and not the sentence of deposition, was lifted.