Selyf ap Cynan

Selyf ap Cynan (or Selyf Sarffgadau) († circa 616) appears in the ancient Welsh genealogies as a seventh-century king of Powys, son and successor of Cynan Garwyn.

His name is a Welsh form of Solomon and appears in the oldest genealogies as Selim. It is said that it had the nickname "Sarffgadau", whose meaning is "battle serpent". According to Annals of Ulster and Annales Cambriae died in the Battle of Chester, fighting against Etelfrido of Bernicia. The Annals of Ulster give him the title of King of the Britons, perhaps because he led a combined force of several kingdoms in that battle.

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