Rhiwallon ap Cynfyn was a notable figure in 11th-century Wales, recognized as a prince of Gwynedd. He was the son of Cynfyn, a ruler who played a significant role in the region's history. Rhiwallon is often associated with the struggles for power among Welsh nobility during a time of political fragmentation. Rhiwallon is also known for his involvement in the conflicts against the Anglo-Saxon incursions. His lineage and actions contributed to the complex tapestry of Welsh history, particularly in the context of the ongoing resistance against external forces. His legacy is part of the broader narrative of Welsh identity and sovereignty.