Lady of the Lake
Dame del Lac, Damoisele del Lac, Damsel of the Lake
There are two distinct Ladies of the Lake in Malory. Very little is said about her in the Arthurian romances, there seem to be three in all, taking the Vulgate into account: one who raised Lancelot in France, one who gave Arthur his sword, and Nimue. Likely all started as one character but, in the present state of the legends, I see nothing for it but to split them.
According to Ulrich von Zarzikhoven, the fairy who raised Lancelot was the mother of Mabuz, and, as Mabuz is thought to be identical with the Celtic god Mabon, this would suggest that the Lady of the Lake in this instance was none other than Morgan Le Fay, for she was, in origin, Mabon's mother, Matrona. It seems highly likely, therefore, that the Lady of the Lake has her origins in a Celtic lake divinity, perhaps of the same kind as the Gwragged Annwn (lake fairies in the modern Welsh folklore), a possibility further supported by the fact that some sources say that she was one of the three queens aboard the ship that ferried the dying Arthur to Avalon.
The French Lady seems to be basically good. So does Nimue; although she imprisons Merlin, she thereafter acts beneficently to Arthur and this court. However, the one who gave Arthur his sword, even in that instance cooperating with Merlin, appears to have been evil. Tennyson makes the Lady of the Lake a good, mysterious, almost angelic benefactress of Arthur, but Vivane (Vivienne) a villainess who seduces and imprisons Merlin as part of her design to bring back Paganism.
For convenience I distinguish them as follows: Viviane (the French Damsel of the Lake, who raised Lancelot), "Nineve" (Malory's first English Lady of the Lake, who gave Arthur his sword), and Nimue (the second English Lady of the Lake, who gained the position after "Nineve's" death and who became benefactress to Arthur's court). Though "Nineve" is never actually named, "Nineve" is a variant of both the names Nimue and Viviane, and it is a handy one for my purpose.
Both Nimue and Viviane are credited with imprisoning Merlin; whereas Viviane must be in France to raise Lancelot, Malory definitely puts Nimue in Britain. Take your choice as to which actually did away with the great necromancer. Viviane definitely, and Nimue apparently, had other damsels of the lake under them. The Vulgate says the Damsels of the Lake owed their knowledge of magic to Merlin; Malory corroborates this as far as Nimue is concerned, but not as far as "Nineve" is portrayed.
Sir Pelleas was given a bejeweled necklace of the Lady of the Lake after he had assisted an old woman across a river. Its enchantment made its wearer unfathomably loved.
The Lake | The Legend of King Arthur