Some scholars have suggested that York remained a significant regional centre for the Britons, based largely on literary evidence. Several manuscripts of the "Historia Brittonum", written c. 830, contain a list of 28 or 33 "civitates", originally used to describe British tribal centres under Roman rule but here translated as Old Welsh ' () and probably indicating "fortified cities". Among these settlements is '". Later, the text states that Ida was the first Anglian king Bernicia and ruler over Cair Ebrauc. These are generally taken as references to a successor to old Roman Eburacum. This mention has led to speculation about Ebrauc in post-Roman times.