Victorian (mostly) Artists of Arthurian Legend

William Dyce (1806-1864)
At the request of Prince Albert, Dyce painted 4 frescoes for Queene's Robing Room, Westminister, to personify British virtues illustrated in Arthurian legend:  Religion, Generosity, Courtesy, Mercy.
Merci (1848) shows Lancelot on his horse sparing the fallen Arthur. 

The Pre-Raphaelites:

The Pre-Raphaelite Brotherhood (or PRB) was a 19th century group of rebellious young artists who, disillusioned with the artistic climate of their day, sought to rediscover the purity of art by creating an entirely new artistic style that drew upon the middle ages, the bible, classical mythology and nature for inspiration, emulating the work of the great Italian artists before Raphael (hence their name: pre-Raphaelite). The PRB only lasted for five or so years, but it served to inspire many other painters such as Lawrence Alma-Tadema and John William Waterhouse throughout the rest of the 19th century and into the early 20th century.  (www.artmagick.com)

Dante Gabriel Rossetti(1828-1882)
Rossetti organized the Pre-Raphaelite Brotherhood.
The Palace of Art
(1854 drawing for the Moxon edition of Tennyson's Idylls of the King)
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The Damsel of the Sanct Grail (1857)
King Arthur's Tomb (detail) 
    (1854 watercolor, only 9"x14", showing Lancelot and Guenever meeting over Arthur's corpse)
How Sir Galahad, Sir Bors, and Sir Percival Were Fed with the Grail, but Sir Percival's Sister Died by the Way (1864 watercolor) 
   

William Morris
Guenevere or La Belle Iseult (1854) 
Morris's only extant oil painting. He abandoned it and it was eventually completed by Dante Gabriel Rossetti and Ford Madox Brown. The painting shows Jane Burden (who was to marry Morris in 1859) in the guise of King Arthur's consort. She stands before a crumpled bed that alludes to her adulterous love affair with Sir Lancelot.
(www.artmagick.com)

Edward Burne-Jones (1833-1898)
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The Beguiling of Merlin (Burne-Jones painted 5 versions of Merlin and Nimue) 
  Last Sleep of Arthur in Avalon
 

William Holman Hunt
Hunt painted various studies of the Lady of Shalott tangled in her loom.
The Lady of Shalott
The Lady of Shalott (Engraving for the Moxon edition of Tennyson's Idylls of the King 1856-57) 
 

Sophie Anderson, French (1823-1903)
Elaine, or the Lily Maid of Astolat (1870)
 

Arthur Hughes (1823-1904)
Knight of the Sun
Sir Galahad
The Lady of Shalott
 

William Waterhouse
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The Lady of Shallot (1888) 
One of the few paintings of the boat segment of Elaine's story which shows her alive.  Waterhouse's sister Mary was the model.

"I am half-sick of shadows," said the Lady of Shalott 
The Lady of Shalott  (1894)

Sidney Meteyard (1868-1947)
"I am half-sick of shadows," said the Lady of Shalott (1913)

Frank Cowper (1877-1958)
The Damsel of the Lake, Called Nimue the Enchantress (1924) 
Four Queens Find Lancelot Sleeping
La Belle Dame Sans Merci  (1926 painting inspired by Keats' poem of the same name)

James Archer
The Death of Arthur (1823) 

John Collier (1850-1934)
Guinivere's Maying

Sir Frank Dicksee (1853-1928)
Le Belle Dame Sans Merci

Edmund Blair Leighton (1853-1922)
The Accolade
A Lady's Favor or God Speed
Stitching the Standard
 

Briton Riviere (1840-1920)
Elaine-`The Dead Steer'd by the Dumb Went Upward with the Flood', from 'Malory's Morte d'Arthur' 

John Spencer-Stanhope
Morgan le Fay
 

John Atkinson Grimshaw (1854-1906)
Elaine

                                Illustrators:
Gustave Dore (1832-1883)
Illustrated 4 poems for Tennyson's Idylls.  Made 36 more drawings, which were copied by engravers and later published all together. 
The Finding of Arthur
Elaine Floats Down to Camelot on a Barge
Lancelot's Remorse
The King's Farewell

Aubrey Beardsley (1872-1898)
Created 500 black & white drawings for J. M. Dent's Le Morte D'Arthur, published 1893-94.  Art Nouveau style.  Victorians were not enthusiastic about his tendency to portray men as passive, androgynous, unheroic beings often reclining, asleep, or naked, while his women and feys were more active.
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How Sir Bedivere Cast the Sword Excalibur into the Water 
How Four Queens Found Lancelot Sleeping
The Lady of the Lake Telleth Arthur of the Sword Excalibur
How Sir Lancelot Was Known by Dame Elaine
  

Julia Margaret Cameron
Tennyson asked her to illustrate his Idylls.  Her photographs used top & side lighting, long exposure, and the wet collodion development process to create an otherworldly aura of the magical past.  Published in 1874.
The Corpse of Elaine in the Palace of King Arthur
Elaine in the Barge
Elaine the Lily Maid of Astalot
King Arthur
King Arthur Lying in a Barge
The Little Novice and the Queen
Vivien and Merlin
Vivien and Merlin
 

N. C. Wyeth
Illustrated Sidney Lanier's The Boy's King Arthur, 1917.
Inside Cover 
And when they came to the sword that the hand held, King Arthur took it up.
He rode his way with the Queen unto Joyous Gard
   Then the king ran towards Sir Mordred, crying, "Traitor, now is thy death day come."
   Then Sir Launcelot saw her visage, but he wept not greatly, but sighed.
 

Good web sites with bibliographies and many more images:

Artmagick's Pre-Raphaelite Collection
Excellent collection of Pre-Raphaelite paintings with biographies of the artists and discussions of some individual paintings.
http://www.artmagick.com

Carol Gerten's Art Gallery
Very large gallery with alphabetical artist index.  Outstanding quality.
http://sunsite.auc.dk/cgfa/

Camelot Project: Artist's Menu
http://www.lib.rochester.edu/camelot/cphome.stm

Celtic Twilight
Large collection, easily accessible, with most images sized to fit inside screen
http://camelot.celtic-twilight.com/artists/index.htm