In the 12th century Geoffrey of Monmouth adapted Gildas' account for his chronicle Historia Regum Britanniae, and thereafter Aurelius Conanus was remembered as a legendary King of Britain.
Gildas discusses Aurelius Conanus in Chapter 30 of his work De Excidio et Conquestu Britanniae, in a section in which he reproves five kings for their various sins.
Historian John Edward Lloyd suggests that the form Caninus, appearing in one important manuscript of De Excidio, may have been a corruption of the more common Cuna(g)nus, or Cynan in Welsh.
[3] As such he may be identified with one of the figures of that era who bore that name, such as Cynan Garwyn of Powys or his relative Cynin ap Millo.
[3] In the 12th century, Geoffrey of Monmouth adapted Gildas' account for his influential pseudohistory Historia Regum Britanniae, adding fictional details and making these contemporary regional rulers successive high-kings of Britain.