The name Cynan Wledig appears in its Latin form as Aurelius Caninus in the De Excidio where it is listed as one of five tyrants alive at the time of Gildas. Their territories were as follows:
? (Aurelius Caninus),
Bartrum suggests Aurelius Caninus can be identified with Cynan Garwyn of Powys, which is plausible. He adds that there is no consensus as to which kingdom he ruled. Gildas’s list follows a geographical progression which suggests Cynan ruled over an area of South Wales. He would have been of gen. 0 or 1, as were the other tyrants, suggesting that he may have been Cynan ap Casanauth Wledig of Powys, see JC20 16b at Sanan ferch Elise.
The five rulers appear in the DEB after the Ambrosius passage. It may be they inherited his kingdom as indicated by:
brenin Emrys y bumran
King Emrys of the Five Parts