Rhys ap Dafydd was the patron of poem 11. No other poems to him survive.
Bartrum gives no genealogy for Rhys himself, but his grand-daughter, ‘Gwenh. Fechan f. Jenkin ap Rhys ap Dafydd ap Rhys of Anhuniog’, is noted in WG2 ‘Cydifor ap Dinawal’ 9D as the wife of Dafydd Llwyd ab Ieuan of Creuddyn.
Rhys held various offices in Cardiganshire local government, and in the commote of Anhuniog in particular, between 1423 and 1439, and he died in 1439–40 (Griffiths 1972: 310). Guto’s poem to him probably belongs to the period 1435–40. On the basis of the reference to [g]oror Peris ‘Peris’s region’ in line 46, Rhys’s home can be located somewhere in the valley of the river Peris which flows into the sea at Llansanffraid near Llan-non in the north of the commote of Anhuniog.
Griffiths, R.A. (1972), The Principality of Wales in the Later Middle Ages: The Structure and Personnel of Government, i: South Wales 1277–1536 (Cardiff)