Whenever I think I’ve written my last word about Belfast, I find there’s more,” says Joan Lingard. “Belfast is my framework for looking out on the world. If you grow up somewhere, you have a world that never leaves you.”

This novelist, who built her reputation as a children’s writer in the 1970s with a series of novels for teenagers about the Troubles, continues to attract full houses at book events north and south of the Ulster border. Her most recent book, Dark Shadows, was published last year and is set in contemporary Belfast, with characters who are impatient at the divisions which plagued their parents (Kevin and Sadie, the Catholic hero and Protestant heroine of Lingard’s best known books), and take steps to rid themselves of the baggage of the past.

Lingard and Belfast go back a long way: she lived there until she was 18, although she was born in Edinburgh, where she now makes her home. A lesser-known novel which introduces young readers to her private city is The File on Fraulein Berg, due to be re-published by Hodder Children’s Books in the New Year.

This book, first published in 1980, is stuffed with snapshots from her childhood: the badly-run minor private school with its grand airs; the public library that used to be a cornershop, with its windows painted brown and greasy books.

The book is set during the Second World War, and the moral is the perils of an over-active imagination, with an added warning against intolerance and hysteria. Kate reads too many library books and convinces her friends that the new German teacher is a spy. By the time the girls discover that Fraulein Berg is actually a Jewish refugee, they have already begun to suffer for persecuting her. “We were mean to some of our teachers - they were mostly not very good - but not on such a grand scale,” admits Lingard.

She wrote her first novel at 11, having run out of Biggles and Chalet School books to read. Her first heroine, Gail, had waist-length plaits (Joan had a pudding-basin cut). At that time, her fictional landscape consisted of rambling houses with treasure-stuffed attics, parents who were summoned overseas by telegram and remote Cornish coves to explore. “I would look down the street in Belfast and see nowhere to go exploring,” she says. “I certainly believed that most of what I read was far more interesting than life in deadly old Belfast. I never thought that I would want to write a single word about where I lived.”

Her childhood seems idyllic in retrospect, partly because her mother was a Christian Scientist. “I was brought up in the belief that there was no pain, disease or death.” When she was 16 her mother died of breast cancer “and my way of life died too, childhood was over”. She gave up writing, which she only took up again in her twenties, and left school at 16 to work as an untrained teaching assistant in a primary school before leaving for Edinburgh.

Belfast only resurfaced in her fiction (35 novels including 13 for adults at the last count) after a prolonged absence. The breakthrough came with The Twelfth Day of July, her first children’s book. Lingard, who had been building a reputation for adult novels alongside bringing up her three daughters, was told that no London publisher would touch a children’s story about religion and politics in Northern Ireland, but Julia Macrae, then a forward-looking editor at Hamish Hamilton, encouraged her to press on. In terms of content, The Twelfth Day of July was a pioneering book; it was also her first commercial success, with readers clamouring for a sequel. “I had to finish their story for myself too.”

There are five books in the series, which see the couple through love across the barricades, family opposition, flight to England and the highs and lows of life together after their secret marriage. They have never been out of print.

Lingard left the couple in the late Seventies with a baby son and a temporarily secure home in Cheshire, but nobody could close the book on the real-life events that had informed their fictional lives. In Dark Shadows, set in Belfast 20 years later, she introduces Jess and Laurie, cousins born a day apart in the same city who do not meet until they are 15. Religion is only part of the problem between their families - class is also an issue.

When Jess and Laurie become friends, they encounter difficulties but not insuperable ones. “Kevin and Sadie have to leave Northern Ireland and their families never change; Jess and Laurie don’t have to leave and are able to bring about reconciliation. Young people want to get on with their lives now and sweep aside the mess their parents have made. That happens worldwide, just as Kevin and Sadie’s predicament is not unique to Belfast - it happens everywhere there are divisions, such as those between Jew and gentile, black and white.”

Dark Shadows was a key book in last year’s Books Across theBorder programme, a series of events about using literature to promote understanding. Joan Lingard was a guest speaker at packed library sessions in Newry in the north and Dundalk in the south.

She relishes her encounters with Northern Ireland audiences, but remembers having to pause on the brink of a story about a friend’s new husband who is an Orangeman. “I thought, ‘Will they laugh at this or will it be awkward?’. Better be careful.”

‘The File on Fraulein Berg’ will be published by Hodder Children’s Books in January 2000. The Kevin and Sadie series and ‘Dark Shadows’ are all published by Puffin.