Clemen, King of Dumnonia
King Cynegils of Wessex took advantage of King Bledric of Dumnonia's death by immediately invading Dumnonia (614). His armies apparently slew 2,065 men of the west at the Battle of Beandun (Bindon, Devon). Bledric's son, Clemen, was thoroughly defeated and was forced to retreat back to Caer-Uisc (Exeter). In later years, he was besieged there by King Penda of Mercia, but the High-King, Cadwallon, arrived to defeat him. The three made an alliance together and marched against the armies of Northumbria who had invaded Gwynedd. The name Clemen may, in fact, be a corruption of Glywys, and hence a confused memory of King Glwys Cernyw.
Generally considered legendary.