Excalibur: a Novel of Arthur is the story of Arthur, King of the Britains, during his tumultuous relationship with Guinevere and his ascent to the throne of High King. Arthur is pitted against his nephew Mordred against a backdrop of warring Christian and Pagan theology. Arthur, tired of politics and weary of war, wishes to avoid conflict but is pressured into war by Mordred. Eventually he kills his nephew and, heartsick, sails away to Avalon with Guinevere.
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