Lancelot in the context of "Guinevere"

Idylls of the King, published between 1859 and 1885, is a cycle of twelve narrative poems by the English poet Alfred, Lord Tennyson (1809–1892; Poet Laureate from 1850) which retells the legend of King Arthur, his knights, his love for Guinevere and her tragic betrayal of him, and the rise and fall of Arthur's kingdom.

The whole work recounts Arthur's attempt and failure to lift up mankind and create a perfect kingdom, from his coming to power to his death at the hands of the traitor Mordred. Individual poems detail the deeds of various knights, including Lancelot, Geraint, Galahad, and Balin and Balan, and also Merlin and the Lady of the Lake. There is little transition between idylls, but the central figure of Arthur links all the stories. The poems were dedicated to the late Albert, Prince Consort.

The Knights of the Round Table (French: Chevaliers de la Table Ronde) are the legendary knights of the fellowship of King Arthur that first appeared in the French-language Matter of Britain literature in the mid-12th century. The Knights are a chivalric order dedicated to ensuring the peace of Arthur's kingdom following an early warring period, entrusted in later years to undergo a mystical quest for the Holy Grail. The Round Table at which they meet is a symbol of the equality of its members, who range from sovereign royals to minor nobles.

The various Round Table stories present an assortment of knights from all over Great Britain and abroad, some of whom are even from outside of Europe. Their ranks often include Arthur's close and distant relatives, such as Agravain, Gaheris and Yvain, as well as his reconciled former enemies, like Galehaut, Pellinore and Lot. Several of the most notable Knights of the Round Table, among them Bedivere, Gawain and Kay, are based on older characters from a host of great warriors associated with Arthur in the early Welsh tales. Some, such as Lancelot, Perceval and Tristan, feature in the roles of a protagonist or eponymous hero in various works of chivalric romance. Other well-known members of the Round Table include the holy knight Galahad, replacing Perceval as the main Grail Knight in the later stories, and Arthur's traitorous son and nemesis Mordred.

Chrétien de Troyes (Modern French: [kʁetjɛ̃ də tʁwa]; Old French: Crestien de Troies [kresˈtjẽn də ˈtrojəs]; fl. c. 1160–1191) was a French poet and trouvère known for his writing on Arthurian subjects such as Gawain, Lancelot, Perceval, and the Holy Grail. Chrétien's chivalric romances, including Erec and Enide, Lancelot, Perceval, and Yvain, represent some of the best-regarded works of medieval literature. His use of structure, particularly in Yvain, has been seen as a step toward the modern novel.

Mordred or Modred (/ˈmɔːrdrɛd/ or /ˈmoʊdrɛd/; Welsh: Medraut or Medrawt) is a major figure in the legend of King Arthur. The earliest known mention of a possibly historical Medraut is in the Welsh chronicle Annales Cambriae, wherein he and Arthur are ambiguously associated with the Battle of Camlann in a brief entry for the year 537. Medraut's figure seemed to have been regarded positively in the early Welsh tradition and may have been related to that of Arthur's son. As Modredus, Mordred was depicted as Arthur's traitorous nephew and a legitimate son of King Lot in the pseudo-historical work Historia Regum Britanniae, which then served as the basis for the subsequent evolution of the legend from the 12th century. Later variants most often characterised Mordred as Arthur's villainous bastard son, born of an incestuous relationship with his half-sister, the queen of Lothian or Orkney named either Anna, Orcades, or Morgause. The accounts presented in the Historia and most other versions include Mordred's death at Camlann, typically in a final duel, during which he manages to mortally wound his own slayer, Arthur. Mordred is usually a brother or half-brother to Gawain; however, his other family relations, as well as his relationships with Arthur's wife Guinevere, vary greatly.

In a popular telling, originating from the French chivalric romances of the 13th century and made prominent today through its inclusion in Le Morte d'Arthur, Mordred is a power-hungry son of Arthur from the incest with Morgause, prophesied by Merlin and destined to bring Britain to ruin. He survives Arthur's attempt to get rid of him soon after his birth and, years later, joins his half-brothers Gawain, Agravain, Gaheris and Gareth in Arthur's fellowship of the Round Table as a young and immoral knight. Eventually, Mordred learns of his true parentage and becomes the main actor in Arthur's downfall. He helps Agravain to expose the illicit love affair between Guinevere and Lancelot and then takes advantage of the resulting civil war to make himself the high king of Britain, ultimately leading to both his own and Arthur's deaths in their battle. Today, he remains an iconic character in many modern adaptations of Arthurian legend, in which he usually appears as a villain and the archenemy of Arthur.

Galahad (/ˈɡæləhæd/), sometimes referred to as Galeas (/ɡəˈliːəs/) or Galath (/ˈɡæləθ/), among other versions of his name (originally Galaad, Galaaz, or Galaaus), is a knight of King Arthur's Round Table and one of the three achievers of the Holy Grail in the Arthurian legend. He is the illegitimate son of Sir Lancelot du Lac and Lady Elaine of Corbenic and is renowned for his gallantry and purity as the most perfect of all knights.

Emerging quite late in the medieval Arthurian tradition, Sir Galahad first appears in the early 13th-century Lancelot–Grail prose cycle. There and in subsequent works, such as the Post-Vulgate Cycle and Le Morte d'Arthur, he has replaced Perceval, introduced in the late 12th century, as the main Grail hero.

The Lady of the Lake (French: Dame du Lac, Demoiselle du Lac, Italian: Dama del Lago) is a title used by multiple characters in the Matter of Britain, the body of medieval literature and mythology associated with the legend of King Arthur. As either actually fairy or fairy-like yet human enchantresses, they play important roles in various stories, notably by providing Arthur with the sword Excalibur, eliminating the wizard Merlin, raising the knight Lancelot after the death of his father, and helping to take the dying Arthur to Avalon after his final battle. Different Ladies of the Lake appear concurrently as separate characters in some versions of the legend since at least the Post-Vulgate Cycle and consequently the seminal Le Morte d'Arthur, with the latter describing them as members of a hierarchical group, while some texts also give this title to either Morgan or her sister.

Le Morte d'Arthur (originally written as le morte Darthur; Anglo-Norman French for "The Death of Arthur") is a 15th-century Middle English prose compilation and 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, including the quest for the Holy Grail and the legend of Tristan and Iseult. In order to tell a "complete" story of Arthur from his conception to his death, Malory put together, 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 Arthurian legend have used Malory as their principal source.

Apparently written in prison at the end of the medieval English era, Le Morte d'Arthur was completed by Malory around 1470 and was first published in a printed edition in 1485 by William Caxton. Until the discovery of the Winchester Manuscript in 1934, the 1485 edition was considered the earliest known text of Le Morte d'Arthur and that closest to Malory's original version. Modern editions under myriad titles are variable, changing spelling, grammar and pronouns for the convenience of readers of modern English, as well as often abridging or revising the material.

Agravain or Agravaine (/ˈæɡrəveɪn/ AG-rə-vain) is a Knight of the Round Table in Arthurian legend, whose first known appearance is in the works of Chrétien de Troyes. He is the second eldest son of King Lot of Orkney with one of King Arthur's sisters known as Anna or Morgause, thus nephew of King Arthur, and brother to Sir Gawain, Gaheris, and Gareth, as well as half-brother to Mordred.

Agravain secretly makes attempts on the life of his hated brother Gaheris starting in the Vulgate Cycle, participates in the slayings of Lamorak and Palamedes in the Post-Vulgate Cycle, and murders Dinadan in the Prose Tristan. In the French prose cycle tradition included in Thomas Malory's Le Morte d'Arthur, together with Mordred, he then plays a leading role by exposing his aunt Guinevere's affair with Lancelot, which leads to his death at Lancelot's hand.