Cadell ap Rhodri

Cadell
King of Seisyllwg
Reign	872 – 909 AD
Predecessor	Rhodri Mawr
Successor	Hywel Dda
Born	c.850
Died	909 AD
Issue	Hywel Dda Clydog
House	House of Dinefwr
Father	Rhodri Mawr
Mother	Angharad

Cadell ap Rhodri (854–909) was King of Seisyllwg, a minor kingdom in southwestern Wales, from about 872 until his death.

Cadell was the second son of Rhodri the Great of Gwynedd and Angharad, a princess from Seisyllwg. In 872 Angharad's brother Gwgon, King of Seisyllwg, drowned without leaving an heir. Rhodri became steward over the kingdom, and while he was unable to make a legal claim to the throne, he was able to install Cadell as king.

He passed it to his son, Hywel Dda, at his death in 909. Cadell and Hywel together also conquered Dyfed in 904–905, establishing Hywel as the king in that region. After his father's death, Hywel ruled the kingdoms jointly as Deheubarth.

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