“FROM: David Nash Ford, Early British Kingdoms: Biographies, 2000, www.earlybritishkingdoms.com/bios/gorlois.html, Internet.

Gorlois, 'Duke' of Tintagel
(Born c.AD 452)
(Welsh: Gwrlais; Latin: Worlesius; English: Wallace)
According to Geoffrey of Monmouth's "History of the Kings of Britain," Gorlois is the Duke of Cornwall in roughly the mid-fifth century. He is the master of Tintagel Castle (Din-Tagell) and is the husband of the ravishing Ygerna (Igraine, in other texts), whose charms were an irresistable temptation to King Uther. Gorlois was slain in combat at St. Dennis (Dimilioc), unsuccessfully defending his lands and wife against Uther's forces.
Gorlois (Gwrlais in Welsh) may have been a governor of Cerniw (Cornwall), the western portion of Dumnonia, under King Erbin. His historicity is confirmed by the evidence of place-names such as Carhurles (Caer-Wrlais) and Treworlas (Tre-Wrlais). Late pedigrees, attributed to Iolo Goch, suggest he was a descendant of Gerdan, a younger son of King Solor of Cernyw (Glywysing). It may either be through coincidence or confusion that Gorlois' ancestry stems from Cernyw (Glywysing), while he lived in Cerniw (Cornwall).
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