Maleagant (alternately Meliagant, Meligaunt, Meliagaunt, Meliaganz, Meliagrance, Mellyagraunce, Mellegrans, etc.) is a villain from Arthurian legend. In a number of versions of a popular episode, Maleagant abducts Queen Guinevere, necessitating her rescue by King Arthur and his knights. The earliest surviving version of this episode names the abductor Melwas. Maleagant debuts in Chrétien de Troyes' French romance Lancelot, the Knight of the Cart, where he is said to be the son of King Bagdemagus, ruler of the otherworldly land of Gorre. However, all surviving versions seem to be later adaptations of a stock narrative of significantly earlier provenance.
The earliest version of the popular abduction of Guinevere episode appears in the early 12th-century Latin Life of Gildas by Caradoc of Llancarfan. In that text Melwas, king of the "Summer Country" (Gwlad yr Haf, Somerset), carries Guinevere off to his stronghold of Glastonbury. Arthur locates her after a year of searching and prepares to storm the castle, but Gildas negotiates her safe return. Melwas also appears in a fragmentary Welsh dialogue, indicating that this story was widely known in Wales. A monumental carving on the archivolt of Modena Cathedral in Italy contains a related scene, in which Arthur and his warriors besiege a castle where a character identified as "Mardoc" sits with "Winlogee", presumably Guinevere.
Maleagant (spelled Meliagant or Meliaganz) first appears under that name in Lancelot, the Knight of the Cart by Chrétien de Troyes, where he brings Guinevere to his impenetrable castle. The queen is rescued by Lancelot and Gawain; this is the first major appearance of Lancelot in Arthurian legend. If he was ever more than an obscure villain, Maleagant's role seems to have diminished as Mordred became more popular; however, Maleagant appears in most accounts of Guinevere's kidnapping. He plays that part in the Lancelot-Grail cycle and Thomas Malory's Le Morte d'Arthur.
In the romance Sone de Nansai, Sone visits an island said to have been Meleagan's. Meleagan's father was King Baudemagus and his grandfather Tadus. Meleagan's island is perfectly square and its walls are made of crystal. There is a palace at each corner and at the center, a fountain wells up through a gilded copper horn. The Sword Bridge connects the island to a causeway, a bowshot away, which leads to the mainland. In Meleagan's day, many men were beheaded there.
- In the Warlord novels, by English author Bernard Cornwell, based on the Arthurian legend, a secondary character named Melwas is mentioned many times, here as the king of the tribe of the Belgae, who inhabited the region roughly corresponding to modern Hampshire with its capital at Venta Belgarum (modern Winchester). At first glance, the only similarity between the legendary character and the fictional one seems to be their common name, but, upon closer inspection, we find some clues that indicate a possible intention of the author of having his fictional Melwas to be his own peculiar version of Maleagant. A couple of similarities include the fact that, in the novels, Melwas is a vassal to King Uther Pendragon (Arthur's father) and, after his death, to his grandson, the child King Mordred, to whom Arthur serves as Regent during his minority, while Maleagant himself was a vassal to King Arthur. Both became members of the Round Table in its respective versions in the novels and in the Arthurian legend, and both betrayed their sovereigns by raising arms against them.
- In the French TV series Kaamelott, Meleagant is a dark and mysterious entity, either a god or a wizard, portrayed by Carlo Brandt. He seems omniscient, able to predict the future and appear in people's dreams. His goal seems to push Lancelot to explore the darkest sides of his personality. Meleagant also pushes King Arthur and the Roman Emperor to commit suicide. While Caesar dies, Arthur survives his suicide attempt.
- He appears in the 1995 film First Knight as a murderous renegade knight of the Round Table, where he is portrayed by Ben Cross.
- Stokstad, Marilyn (1991), "Modena Archivolt", in Lacy, Norris J., The New Arthurian Encyclopedia, New York: Garland, pp. 324–326
- Loomis, p. 359.
- Loomis, p. 211.