Dafydd was arguably Wales' greatest poet. He was a contemporary of Chaucer: being born sometime before 1340 (probably at Llanbadarn near Aberystwyth) and dying around 1380. He is buried beneath the yew tree at Ystrad Fflur, the most beautiful located of the Welsh Cistercian foundations. Dafydd was associated with the development of the cywydd and the introduction of new themes and attitudes in to Welsh poetry: the latter a point of contention (in verse) with other Welsh poets such as Gruffydd Gryg. His work shows both specific influences ("Roman de la Rose", Ovid's "Armores") and the more general influences of the polyglot character of the community in which he was brought up.. His work exhibits a complex but graceful style, concern with nature and love rather than with heroic martial deeds, and has references to Classical and Italian poetry.
Some of his themes recall those of the troubadours and perhaps derive indirectly from them. He was born into an influential Dyfed family, and is traditionally believed to have led a life packed with amorous adventures. He wrote in the cywydd metre, which he perfected.