Juliet Gardiner brands the 1930s the ‘forgotten decade’ on the cover of her latest book, The Thirties: An Intimate History. She does so partly because the ten-year-period of art deco and swing, of hunger marches and a suburban housing boom, is overshadowed now by its terrible finale — its last, anguished year in which Britain found itself engaged, once more, in a calamitous conflict with Germany.

The Thirties are all too often seen as just a ‘curtain raiser’ to the main drama of the Second World War, she says. But it is also a greatly misunderstood decade. “I felt it was a neglected period,” says the historian, speaking to The Oxford Times ahead of her appearance at the Oxford Literary Festival on March 25.

“A lot has been written about the 1930s, but I felt it had rather got into a rut. People only ever talk about it as the ‘low, dishonest decade’ [WH Auden’s famous phrase, conveying the false hope people had about averting the war] or it was all about having a Baby Austin in your garage. I wanted to explore the decade more.”

At almost 1,000 pages, her book is certainly a thorough exploration. Reviews have mostly glowed, however, with critics wondering at, not snoring at, the level of detail. This is perhaps because it revolves around the lives of real people — from wretchedly poor Welsh inhabitants of former mining towns to the increasingly well-off owners of suburban semis — and a compelling sense of human drama buoys readers along.

“I subtitled the book An Intimate History because I show the lives of people,” she explains. “What’s important isn’t just the major events of the 1930s but what people thought about these events. Also, what people thought about their homes, their children, love, sex, cinema and so on.”

Although her vast, sprawling narrative takes a panoramic view of the 1930s, she believes that Oxford was a microcosm of the decade’s contradictions. As well as dole queues and the depression, there was also rising wages and commerce in full swing, with an outlet of Woolworths springing up in every town centre and ordinary people able to afford their own car.

“William Morris’s car factory in Cowley was at the forefront of this new Britain: JB Priestley’s ‘Third England’,” she says. “Oxford was very much at the heart of this; an engine of change.”

Nowhere was the chasm between the haves and have-nots better expressed than in the case of the Cutteslowe Wall, erected in Summertown in 1934. The seven-foot-tall brick walls, built to separate a council housing estate from an upmarket private development, became an enduring symbol of the British class system: “the most concrete expression of class division that you can imagine”, she says.

Politics of the extreme left and right found root in 1930s Britain. While Oswald Mosley’s Blackshirts gave voice to Fascism, Communists were also a vociferous minority. The book draws attention to Oxford University’s far-left ‘October Club’, whose members included Philip Toynbee, first communist President of the Oxford Union (and father of left-wing commentator and journalist Polly Toynbee). She also recounts the support shown by Oxford University students for the hunger marchers coming through the town in 1934, much to the anger of a government minister, who castigated the students in the House of Commons.

Both these sections counter the Brideshead stereotype of Oxford students as upper-crust champagne-quaffers with no thought for the working man.

“I do think Oxford took the temperature of the nation,” she said. The Oxford Union debate in 1933, when students voted not to fight for king and country, heralded a new age where unthinking deference to the crown was no longer de rigeur, she believes.

Oxford is not just a handy metaphor for what was going on in Britain during her chosen decade; she has done much of her work in the city, having taught history at Oxford Brookes University before leaving in 2001 to become a full-time writer. She had a flat in Jericho and still frequently travels from her home in East London to research in the Bodleian Library or the Oxfordshire Record Office.

Almost all her academic career has concentrated on the first half of the 20th century. She is an acknowledged expert, advising on period dramas, including the film adaptation of Ian McEwan’s Atonement. I wonder why she has fixed so steadfastly on this period.

“I like the fact that these are the fingertips of history. You feel that people are only just a stretch away. You’ve got the luxury of feeling that you half understand people, but at the same time you mustn’t make the assumption that you know too much. And you’ve always got the feeling that you’ll find something new: someone’s diaries will emerge, for instance.”

* The Thirties is published by Harper Press at £30. Juliet Gardiner will be at the Oxford Literary Festival on March 25.