He is mentioned as one of the five British poets of renown, along with Talhaearn Tad Awen ("Talhaearn Father of the Muse"), Aneirin, Blwchfardd, and Cian Gwenith Gwawd ("Cian Wheat of Song"), in the Historia Brittonum, and is also mentioned in the collection of poems known as Y Gododdin.
Aparece mencionado como un dos cinco poetas britóns de renome, xunto con Talhaearn tad Awen ("Talhaearn Pai da Musa"), Aneirin, Blwchfardd, e Cian Gwenith Gwawd ("Cian Trigo de Canción"),  na Historia Brittonum, e tamén se menciona na colección de poemas coñecida como Y Gododdin.