Disambiguation: For the DC Comics version of this character, see Vivienne Inwudu.
In Medieval Literature
The Lancelot-Grail Cycle provides a back-story for the Lady of the Lake, Viviane, in the prose Merlin section, which takes place before the Lancelot Proper, though it was written later. There, Viviane learns her magic from Merlin, who becomes enamored of her. She refuses to give him her love until he has taught her all his secrets, after which she uses her power to trap him either in the trunk of a tree or beneath a stone, depending on the story and author. Though Merlin, through his power of foresight knows beforehand that this will happen, he is unable to counteract Viviane because of the "truth" this ability of foresight holds. He decides to do nothing for his situation other than to continue to teach her his secrets until she takes the opportunity to entrap and entomb him in a tree, a stone or a cave.
The Post-Vulgate Cycle's second Lady of the Lake is called Ninianne, and her story is nearly identical to the one in the Lancelot-Grail, though it adds her bestowal of the magic sword Excalibur to Arthur. Sir Thomas Malory also uses both Ladies of the Lake in his Le Morte d'Arthur; he leaves the first one unnamed and calls the second one Nimue. Malory's original Lady is presented as an early benefactor of King Arthur who grants him Excalibur when his original sword is damaged. She is later beheaded by Sir Balin as a result of a kin feud between them (she blames him for the death of her brother and he blames her for the death of his mother) and a dispute over an enchanted sword.
Both characters appear in many other episodes of Malory's work. Each time the Lady reappears, it is at a pivotal moment of the episode, establishing the importance of her character within Arthurian literature, especially Le Morte d'Arthur. In that work, she transcends any notoriety attached to her character by aiding Arthur and other knights to succeed in their endeavors. After enchanting Merlin, Malory's Nimue replaces him as Arthur's adviser. She becomes the lover and eventual wife of Sir Pelleas and mother to his son Guivret. After the Battle of Camlann, she reclaims Excalibur when it is thrown into the lake by Sir Bedivere. Nimue is one of the four magical queens who bear the wounded Arthur away to Avalon, a setting tied to the Lady of the Lake in some literary traditions.
The Lady of the Lake was the foster-mother of Sir Lancelot and raised him beneath the murky waters of her Lake. She is, however, best known for her presentation to King Arthur of his magical sword Excalibur, through the intervention of the King's druidic adviser, Merlin (Myrddin) who was constantly worried that his monarch would fall in battle.
Merlin had met the Lady at the Fountain of Barenton (Brittany) and fallen so deeply in love with her that he agreed to teach her all his mystical powers. The lady became Merlin's scribe, who recorded his prophecies, as well as his lover. Unfortunately however, over the years, the Lady became so powerful that her magical skills outshone even her teacher and she imprisoned him in Glass Tower (or similar dungeon). To some extent she stepped into Merlin's role at King Arthur's side, but the old man's removal contributed considerably to the great monarch's downfall. The Lady of the Lake was eventually obliged to reclaim her sword when Arthur was fatally wounded at the Battle of Camlann and Excalibur was hurled back to misty waters. She was later one of the three Queens who escorted the King to Avalon.
The Lady of the Lake is usually referred to by various spellings of the names Nimue or Vivienne. Nimue is thought to be related to Mneme, the shortened form of Mnemosyne, one of the nine water-nymph Muses of Roman and Greek Mythology who gave weapons, not unlike Arthur's sword, to the heroic Perseus. Vivienne betrays the Lady's Celtic form, for "Vi-Vianna" probably derives from "Co-Vianna", a variant of the widespread Celtic water-goddess, Coventina. Remembering Latin pronunciation, this name probably relates to Merlin's original partner in early poetry, his wife Gwendoloena. Thus Gw-end(-ol)-oena = Cov-ent-ina. There have also been attempts to show Vivienne as a corrupt form of Diana or Rhiannon. Though possible, these theories seem unlikely.
Water deities were extremely popular with Celtic Society for they controlled the essential essence of life itself. The spontaneous movement of springs, rivers and lakes clearly showed the supernatural powers of the goddesses who lived within; and offerings at such aquatic features were commonplace, especially of weapons and other valuables. The practice continues today at wishing wells across the country, and the Lady of the Lake is remembered as "Lady Luck"!
Her names clearly reveal this Lady to have been the Celtic Water-Goddess Coventina (presumably identified by the Romans with their Mnemosyne). This lady was worshipped throughout the Western Roman Empire, in Britain, the Narbonne area of Gaul and North-Western Iberia too. She is most celebrated for her shrine at Brocolitia (Carrawburgh) on Hadrian's Wall. Here a quadrangular temple surrounded a central pool fed by a sacred spring. Coin, jewellery and small bronze figurine offerings have been excavated as well as numerous altars dedicated by the local soldiers.
Since the Lady of the Lake's place as Merlin's student and lover was largely overtaken by Morgan Le Fay, a lady whose very name in Breton indicates a water-nymph, it seems that the two were aspects of the same character. Indeed, as both appear among the three queens who escort Arthur to Avalon, she no doubt had a third aspect making up the well-known theme of a Celtic Triple-Goddess.
In Marvel Comics
A magical being, the Lady of the Lake has encountered some superheroes from around the world, most notably Captain Britain, the Black Knight and their friends. More recently she fought alongside Captain Britain and his team during the Skrull invasion on Brittain and the world. It seemed that she was killed by a Skrull with an anti-magic gun. She however showed up more recently in the pages of Journey into Mystery, so her apparent death was a mistake.