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It befell in the days of Uther Pendragon, when he was king of all England, and so reigned, that there was a mighty duke in Cornwall that held war against him long time. And the duke was called the duke of Tintagil.

Sir Thomas Malory (1871). “Morte D'Arthur: Sir Thomas Malory's Book of King Arthur and of His Noble Knights of the Round Table”, p.25
It befell in the days of Uther Pendragon, when he was king of all England, and so reigned, that there was a mighty duke in Cornwall that held war against him long time. And the duke was called the duke of Tintagil.