Baron of Cymmer-yn-Edeirnion (or Kymmer-yn-Edeirnion), in the county of Merioneth, is a dormant title used by the senior male-line descendants of Owain Brogyntyn, youngest son of Madog ap Maredudd king of Powys. Owain Brogyntyn divided his lands equally between his three sons on his death, and his eldest son, Iorwerth, inherited lands centred on Cymmer (or Kymmer), in the parish of Llangar and commote of Edeirnion (part of Merionethshire). His son, Gruffydd ab Iorwerth, fought against Edward I during his invasion of Wales. After the Conquest of Wales, Gruffydd came "into the King's peace", and on 22 July 1284, had his lands confirmed by Edward I per baroniam, 'just as his ancestors had held them', thereby creating him a baron in the English feudal baronage. The first surviving use of the t