Did Guinevere kill King Arthur

Answer 1

It sort of depends on whether you want to a direct answer or not. Directly, no Guinevere was not responsible for Arthur's death. I mean she was not the one who dealt the mortal blow but it was her and her affair with Lancelot that kept the Holy grail away from Camelot and removed Camelot from it's protection. So in a way Guinevere set the stage for Arthur's death at the hands of his son/nephew Mordred.