Cadell ap Rhodri

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 King 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.

After his father's death, Hywel ruled the kingdoms jointly as Deheubarth.