Cadafael Cadomedd ap Cynfeddw

Cadafael ap Cynfeddw (English: Cadafael son of Cynfeddw) was King of Gwynedd (reigned 634 – c. 655). He came to the throne when his predecessor, King Cadwallon ap Cadfan, was killed in battle, and his primary notability is in having gained the disrespectful sobriquet Cadafael Cadomedd (fully translated into English: Battle-Seizer the Battle-Decliner).

Unusual for the era, King Cadafael was not a member of one of the leading families of Gwynedd. His name appears in the Welsh Triads as one of the "Three kings, who were of the sons of strangers" (sometimes referred to as the "Three Peasant Kings"), where he is identified as "Cadafael, son of Cynfeddw in Gwynedd".

Cadafael's reign was a critical time for the future of the Cymry (i.e., the Welsh and the Brythonic 'Men of the North' taken together, exclusive of all others). There was an alliance of the Cymry with Penda of Mercia initially forged by Cadwallon ap Cadfan, and there was ongoing warfare against the then-ascendant Kingdom of Northumbria.

Though the alliance was effective and enjoyed several notable successes, it would end disastrously with the death of Penda and a Northumbrian supremacy both in the north and in the English Midlands. The kingdoms of Pengwern, Manaw Gododdin, Gododdin, and Rheged would be permanently obliterated. The kingdoms of Gwynedd, Powys, and Alt Clud would be diminished. The blame for it fell hardest on Cadafael's reputation.

When Cadafael's predecessor Cadwallon ap Cadfan came to the throne c. 625, the fortunes of the Kingdom of Gwynedd were at low ebb. Edwin of Northumbria was everywhere successful, having conquered and absorbed the Cymry of Elmet and decisively defeated the Welsh at Chester in 616. Edwin would launch a successful occupation of Lindsey in 625, and he invaded and defeated Wessex in 626. He would also invade and occupy Anglesey, besieging Cadwallon on Ynys Seiriol (English: Island of Saint Seiriol), off easternmost Anglesey, and forcing him to flee to Ireland.

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