The Lancelot-Grail Cycle, also known as the Vulgate Cycle or the Pseudo-Map Cycle, is an early 13th-century French Arthurian literary cycle consisting of interconnected prose episodes of chivalric romance originally written in Old French. The work of unknown authorship, presenting itself as a chronicle of actual events, retells the legend of King Arthur by focusing on the love affair between Lancelot and Guinevere, the religious quest for the Holy Grail, and the life of Merlin. The highly influential cycle expands on Robert de Boron's "Little Grail Cycle" and the works of Chrétien de Troyes, previously unrelated to each other, by supplementing them with additional details and side stories, as well as lengthy continuations, while tying the entire narrative together into a coherent single tale. Its alternate titles include Philippe Walter's 21st-century edition Le Livre du Graal.

Le Morte d'Arthur is a 15th-century Middle English prose reworking by Sir Thomas Malory of tales about the legendary King Arthur, Guinevere, Lancelot, Merlin and the Knights of the Round Table, along with their respective folklore. In order to tell a "complete" story of Arthur from his conception to his death, Malory compiled, rearranged, interpreted and modified material from various French and English sources. Today, this is one of the best-known works of Arthurian literature. Many authors since the 19th-century revival of the legend have used Malory as their principal source.