With a career encompassing 25 years that included five novels, a handful of plays and thousands of drawings, paintings and sketches, why isn't Mervyn Peake a more celebrated English literary and artistic hero? A cult figure today, Peake is best known for Gormenghast, his bleak but compelling gothic fantasy trilogy published in the 1940s and '50s about the hierarchy of a fictional castle, Gormenghast, and the Machiavellian machinations of its inhabitants. But he was also an accomplished illustrator, painter and war artist. "If somebody's good at everything, then they're never taken seriously, are they?" muses Chris Beetles, owner of the eponymous gallery in St. James' in London that hosted a rare exhibition of Peake's art in October.

It is precisely this failure to acknowledge Peake's breadth of talent that Mervyn Peake: The Man and His Art, a new and comprehensive guide to his career, seeks to redress. In 1998, Peake's son Sebastian met Alison Eldred, an avid collector of Peake's artworks at Beetles' gallery, and over dinner the new acquaintances decided to compile and edit a book which, says Sebastian, would show his father's "eclecticism and breadth to a new generation."

Though Peake's talent is indisputable, the source of his marvelously twisted imagination is elusive. Unlike the early years of many masters of the macabre, Peake's childhood was happy and contented. The son of a doctor with the London Missionary Society, Peake was born in Kuling, China, in 1911 and lived there until he was 11 years old. As a boy, he learned 600 basic Mandarin characters from a Chinese calligrapher, causing later observers to remark on the strange way he held his pen. After his family returned to England, Peake finished his education at Croydon School of Art and the Royal Academy Schools.

Early in his career, Peake became a documentary war artist during World War II. This experience appears to have pushed his world view and his art into a considerably darker realm. In June 1945, he was among the first British civilians to visit the liberated concentration camp at Belsen, Germany. Most of the former prisoners he saw there were too sick to be evacuated. The stark poems and drawings he made about these victims literally dying before his eyes are nearly too harrowing to bear. Returning to Britain, he finished the first Gormenghast book in 1946 and spent the next 20 years as a writer and illustrator, contributing art to the tales of the Brothers Grimm, Treasure Island and Dr. Jekyll & Mr. Hyde.

While his style is similar to American contemporary Edward Gorey, Peake's bizarre sensibilities were less cruel. He enjoyed great critical acclaim as an artist during his career — he was commissioned by the Queen Mother to do illustrations for her grandson Prince Charles' nursery in the 1950s — but he was largely ignored by the literary observers of the time. Kingsley Amis once called Peake "a bad fantasy writer of maverick status."

This book shows just how wrong Amis and his cohorts were. The heavily illustrated tome punctuates examples of Peake's art and excerpts of his writing with purely biographical chapters. Cartoonist Chris Riddell of the Observer Sunday newspaper, Lord of the Rings illustrator John Howe, and others who have been influenced by Peake contribute a range of essays and analysis as well.

Fantasy and science fiction author Michael Moorcock, who contributes an introduction to the book, says: "Peake is in the great tradition of idiosyncratic English writers. His poetry and fiction, like theirs is sui generis and, like his drawing and painting, reveals authentic genius." Comic-book writer Alan ( Watchmen, Lost Girls) Moore calls Peake "probably one of the finest writers in the English language," but says literary snobbery that considers fantasy a lesser art form has contributed to his neglect.

Already at an ebb in his career, Peake developed Parkinson's disease in 1956. Despite attempts to improve his health with electroconvulsive therapy — in which high-voltage electricity is passed through the brain — he died in 1968 at the age of 57. His wife Maeve Gilmore, almost destitute after he died, went to the Tate Gallery to sell her husband's body of work. She was offered £1,500 for the complete collection. Disgusted, she stormed out. If there is any justice, Mervyn Peake: The Man and His Art may well ensure that such snubs are not repeated.

• JOEL MEADOWS
• The Man and His Art rescues a nearly forgotten genius from obscurity