[1] The Latin Life of Gildas by Caradoc of Llancarfan describes Hueil as an "active warrior and most distinguished soldier", who led a number of violent and sweeping raids from Scotland down into Arthur's territory.
Giraldus Cambrensis alludes to this tradition, claiming that Gildas destroyed "a number of outstanding books" praising Arthur after hearing of the death of his brother.
A variation of Hueil's death, chronicled by Elis Gruffudd, is as follows: Kaw o Brydain was the name of a chieftain who ruled over Edeirnion, in North Wales.
The Welsh Triads refer to Hueil as one of the three "battle-diademed" warriors alongside Cai and Drustan, but inferior to Bedwyr.
Hueil is further mentioned in the late twelfth century Englynion y Clyweit, a collection of proverbial englyns attributed to various historical and mythological heroes.