Born: September 19 1947;

Died: May 24 2015

Tanith Lee, who has died aged 67, was an inventive and prolific writer, chiefly of fantasies, though in the course of some 90 novels and 300 short stories she also ventured into science fiction, horror, the reinvention of fairy-tales, historical fiction, children's and young adults' literature; she also wrote two episodes of the cult BBC TV series Blake's 7.

The sheer variety and range of her output was perhaps actively unhelpful in her career; readers who admired, or even adored, some of her work did not necessarily warm to other books.

Then there was the matter of her style, which was lush and baroque, but not always straightforward for the reader. For the most part, she avoided the most common sins of fantastic literature: cliché, an excess of the fey and cod-archaisms, but her prose was always self-consciously evocative and poetic. For her fans, it was one of her foremost virtues; others found it excessively rich fare.

Her settings and atmospheres were strongly in the tradition of "the Weird", owing much to the influence of writers such as Lord Dunsany and his mystical countryman � (George William Russell), C.S. Lewis and Jack Vance. Her own work, like that of Angela Carter, often commandeered the tropes of mythology and fairy tale to explore sexuality, identity - especially feminine identities - mortality and isolation.

One of Tanith Lee's prominent themes was the moral and erotic development of characters placed in hostile, or at least unpredictable, worlds which the heroine (or hero) comes, if not to control, at least to meet on her own terms through a deliberate effort of the will.

From the mid-1970s, when she published her first adult novel, The Birthgrave, which was nominated for a Nebula Award, and became a full time writer, most of Lee's books enjoyed a respectable degree of commercial and critical success. But despite having had "quietly phenomenal sales, now and then", in recent years she found it increasingly difficult to interest publishers in her work. Most of her backlist is now out of print.

In 2012 she told an interviewer: "most of the so-called big publishers are unwilling even to look at a proposal. They aren't interested in seeing anything from me, not even those houses I've worked with for many years ... I can only conclude (without knowing any figures) that a lot of this is financial. I have had people say to me, 'We would like to publish this, but though it would sell, it wouldn't sell enough. And so they won't let us buy it'."

Tanith Lee was born on September 19 1947 in north London, to Bernard and Hylda Lee. Her father's name led to a persistent rumour that she was the daughter of the actor who played M in the Bond films; in fact he and his wife were professional ballroom dancers, and the family moved around a great deal in Tanith's early childhood.

Partly because of her intermittent schooling and undiagnosed dyslexia, she could not read until she was eight, when her father (an avid fan of popular fiction) finally took her in hand. By the next year, she was writing fiction herself, and never stopped. She had better teaching at Catford Grammar School, and left to work as a librarian.

In her mid-20s, she had a year at Croydon Art College, but she never had any doubt that she was a writer first and foremost. Her first book was The Dragon Hoard (1971), a children's book followed by a collection of short stories, Princess Hynchatti and Some Other Surprises (1972) in which her penchant for subverting fairy tales was apparent (the prince marries the witch). She illustrated Animal Castle (1972) herself and produced several other juvenile titles.

When DAW published The Birthgrave she was able to write full-time, and followed it with the sequels Shadowfire and Quest for the White Witch. The sequence had begun (as many of her books did) with a single striking image - in this case of an albino heroine lying in a volcano - which she then developed by writing in longhand; in her 20s and 30s she often wrote several thousand words a day, and once produced a short story in four hours and a novel in less than a fortnight.

The Birthgrave trilogy could be read as science fiction or fantasy, as could Don't Bite the Sun and its sequel Drinking Sapphire Wine, which had something in common with Michael Moorcock's Dancers at the End of Time sequence. A Young Adult trilogy begun in 1978 was assembled as Dark Castle, White Horse in 1986, while the adult fantasy sequence Tales from the Flat Earth (which owed much to Vance) and began with Night's Master in 1978 ran to five volumes, including a collection of short stories, Night's Sorceries (1986).

Her other most notable books included Sabella or the Blood Stone (1980); The Silver Metal Lover, about a woman's love for an android, and its sequels; an alternative world sequence set in Paris (Paradys), and another series, from 1998-2003, which did the same for Venus (Venice). The Gods are Thirsty was a historical novel set at the French Revolution. In 2004, as Esther Garber, she published two lesbian novels.

Her short stories were some of her finest work; the best collections include Dreams of Dark and Light (1986) and Women as Demons (1989), and 2009's selected stories in two volumes: Tempting the Gods and Hunting the Shadows.

Tanith Lee was married to the writer and visual artist John Kaiine in 1992. She won the British Fantasy Award for Death's Master in 1980 - the first woman to win - and several World Fantasy Awards, including a Lifetime Achievement Award in 2013. She was a voracious reader, fond of films, music and football and a devoted fan of Doctor Who. She died, after a long illness, on May 24.