Gwynllyw was the son of King Glywys, whose powerful kingdom of Glywysing was centered on Glamorgan, and supposedly extended as far as eastern Carmarthenshire, and he was a descendent of Macsen Wledig according to some accounts.
Gwynllyw was the son of King Glywys, whose powerful kingdom of Glywysing was centered on Glamorgan, and supposedly extended as far as eastern Carmarthenshire. He was a descendent of Macsen Wledig according to some accounts.