This thesis focuses on the use of folklore in Arthurian literature. In the first chapter I give an introduction to the Arthurian tradition. I then examine the use of folklore in three modern Arthurian works, Alfred Lord Tennyson’s Idylls of the King, Terence Hansbury White’s The Once and Future King, and Mary Stewart’s The Merlin Trilogy, which consists of The Crystal Cave, The Hollow Hills and The Last Enchantment. These authors use folklore in different ways and are strongly influenced by their respective time periods, but still draw on the same traditions and share a common frame of reference. A significant body of folklore has grown up around Arthur. I also examine how originally unrelated legends and folk-tales have come to be attached to him and also how characters from Arthurian legend have been incorporated into existing folklore. The thesis looks at both general and Arthurian folklore. The use of folklore and legendary material in literature helps preserve it. The inclusion of folklore in modern works, for instance Arthurian works or fantasy literature in general, makes it easily accessible to new generations of readers, who are thus introduced to a part of their cultural heritage which they might not otherwise be aware of. The use of folklore adds a non-realistic, “magical” aspect to a work while at the same time placing it within the context of Arthurian legend in particular and British cultural history in general.