As Dickens, Thackeray, Eliot, and Tennyson did in letters, the Pre-Raphaelites defined the Victorian age with paintbrush and canvas. Scandalous in their time, their moral seriousness about art was itself deeply Victorian, however much the public thought otherwise. They were every bit as didactic as any preacher. Intensely English, mixing Christian religious allegory with fairy tales, literary and mythic themes — Arthurian legend provided a deep wellspring of imagery — with a simmering sensuality, the Pre-Raphaelite Brotherhood sought to reinvigorate the pictorial arts.

Rejecting sterile academic convention, which, they charged, stressed mannered artifice at the expense of ‘‘truth,’’ they took their example from the 14th and early 15th century Italian painters who came before Raphael. (Like many avant-gardes, the way forward was to look backward.) Fidelity to nature was one of their creeds: In his famed {I cut date} painting of Ophelia’s drowning, John Everett Millais was said to have scoured the English countryside for just the right brook — only to complain when swans ate the floating plants as he painted them.

Edward Burne-Jones (1833-1898), the subject of Fiona MacCarthy’s acute biography, ‘‘The Last Pre-Raphaelite,’’ was part of the Brotherhood’s later phase. Like Millais, he too was committed to ultra-realistic treatment of the details. For his sequence about Sleeping Beauty, ‘‘Briar Rose,’’ Burne-Jones wrote a friend wondering ‘‘if in the woods near you there are tangles of briar rose — and if deep in some tangle there is a hoary, aged, ancestor of the tangle — thick as a mist and with long horrible spikes on it.’’ Yet like his confreres, Burne-Jones mixed fanatical particulars with stagy, almost dreamlike scenes.

A bridge between the Pre-Raphaelites and the fantastical realms of Aestheticism and Symbolism, Burne-Jones stood against the age. His admirer Oscar Wilde recalled him ‘‘saying to me ‘the more materialist science becomes, the more angels shall I paint: their wings are my protest in favour of the immortality of the soul.’’’ A bearded, charming, mercurial man prone to neurotic fits, Burne-Jones believed in chivalric codes, and the ideal of the artist-craftsman. Canvas was not his only medium: He was equally adept mosaics, tapestries, tile, and stained glass windows, which can be found on churches across England.

Looking back to medieval ideals of craftsmanship, Burne-Jones mounted a ferocious critique of his times through a cult of beauty. ‘‘He believed boldly in the power of art to counteract the spiritual degradation, the meanness and corruption he saw everywhere around him in the ruthlessly expansionist, imperialistic Britain of the nineteenth century,’’ MacCarthy observes. Burne-Jones was ‘‘the licensed escapist of his period, penetrating an art of ancient myths, magical landscapes, insistent sexual yearnings, that expressed deep psychological needs for his contemporaries.’’

Like many biographies today, ‘‘The Last Pre-Raphaelite’’ is a tad overlong and nearly bursting at the seams. But MacCarthy, a noted biographer and art critic, writes with such command of her material that the length of her book can be easily forgiven. John Ruskin, Burne-Jones’s mentor and the greatest art critic of the age, once told him ‘‘I want to reckon you up and it’s like counting clouds.’’ MacCarthy herself concedes Burne-Jones ‘‘prevaricates and teases, tries to slip away.’’ But he does not elude her grasp. From his boyhood in the industrial city of Birmingham, to his education at Oxford, his journeys to Italy with Ruskin, who would push him to study the Italian masters, then his in career London and beyond, as well as his troubled emotional life — Burne-Jones was forever falling in love with young ingénues and artists’ models — MacCarthy gives us a full, fair, and splendidly rich portrait of Burne-Jones the artist and man.

At Oxford, Burne-Jones had intended to join the clergy; in the end, he traded Christianity for the religion of art. At university, Burne-Jones made one of the decisive friendships of his life: William Morris, who became a collaborator and close friend. (Morris got the MacCarthy treatment in her door-stopping 1994 bio.)The push-pull between Morris — poet, textile designer, typographer, interior decorator, radical utopian — and Burne-Jones is a defining feature of the book. But where Morris saw revolutionary potential in an armoire, Burne-Jones frowned on his friend’s hard-charging political campaigning. Burne-Jones thought the artist’s place should be in the studio, where he could continue his ‘‘quest for ideal beauty in a corrupt and apathetic world.’’ His west London house The Grange, became one of the HQs of Pre-Raphaelite circles.

MacCarthy is excellent on Burne-Jones’s phenomenal output, which almost defies belief. His paintings offer up alternative worlds of enchanted grace, perhaps none more so than ‘‘The Golden Stairs’’ (1880), with its evocation of young female beauty in motion. The painting became a touchstone of the Aesthetic movement of the 1890s. But the artistic children he spawned often appalled Burne-Jones, however much he pushed Pre-Raphaeletism towards the 20th century. Aubrey Beardsley’s sexual grotesques mortified him. Burne-Jones once mused, ‘‘Lust does frighten me ….. I don’t know why I’ve such a dread of lust.’’ He knew first hand of sexual yearning — he nearly wrecked his marriage when he pursued the fiery Maria Zambaco, a notorious Pre-Raphaelite ‘‘stunner.’’ In his art, Burne-Jones could modulate what he could not in life.