This lengthier treatment of the section of the Ravenna Cosmography dealing with Britannia than any undertaken previously has, in passing, called into question a number of accepted hypotheses about the author, his methods and his sources. As noted a number of times above, the Cosmographer may well have been a poor copyist, working in an era of declining academic standards. He had little understanding of the materials in front of him, but he was not completely incompetent or without method. Although he does not seem to have attempted a systematic listing of places in Britannia by following the main road system of the former Roman province, for instance, he did organise his readings from the postulated map source in discernible groups.
This is particularly clear in that part of the island for which the Antonine Itinerary has enabled us to identify many Romano-British placenames with locations known to have been occupied at some point during the first to fourth centuries AD. There is no reason to suspect that the Cosmographer abandoned this method in those areas not also served by the Itinerary. The comment of Rivet and Smith (1979, 193) that “the Cosmographer … did not realise that his map had been chiefly designed to show the Roman road system” may be near the truth, but does not sufficiently give credit to the system he evidently did follow.