They may not be up there with the Dead Sea scrolls, but the contents of a tattered brown leather suitcase must still rank among the world’s greatest literary finds. The case belonged to the writer Irène Némirovsky, and it contained the sensation of 2004: the two-part novel Suite Française, which tells, in vivid prose, the story of the early days of the second world war in France, and of the reaction of the French to the German invasion. Left unfinished in 1942 – when the author was arrested and taken to Auschwitz, where she died – it was hailed as a masterpiece by critics and became a best-seller in more than 25 countries. Now another gem from the same suitcase is about to be published, a novella called Fire in the Blood. As with the second part of Suite Française, it is set in Issy-l’Evêque, the village in Burgundy where Némirovsky fled with her family after the fall of Paris.

She was born in Kiev in 1903, the daughter of a successful Jewish banker. The family lived in Russia until 1918, when they fled the revolution, first to Finland, then to France. Némirovsky married a banker, Michel Epstein, and they had two daughters. Her first novel, David Golder, was an instant success, launching her into the heart of Parisian literary life. She continued to produce novels and newspaper books and articles, sometimes for the right-wing press, for which she has been criticised. She had an uncomfortable relationship with her own Jewish roots. In David Golder, for example, the title character is a Jewish banker, and her portrayal of him is at times deeply unsympathetic.

Némirovsky formed a strong emotional attachment to her new homeland. “She loved France,” says her daughter, Denise Epstein. “She loved the French culture. When my grandfather suggested we all go to America to avoid the Nazis, she refused.” Némirovsky wanted to make her family’s life in the country permanent. She applied for French citizenship, which was still pending when she died. In another move that has since proved controversial, she converted her children to Catholicism; yet that saved their lives, as they fled the Nazis during the war under the protection of Catholic guardians. On July 13, 1942, she was arrested for being a “stateless person of Jewish descent”, interned at Pithiviers, a French concentration camp, then transported to Auschwitz, where she died a month later in the infirmary, officially of typhus, aged 39.

Némirovsky had the idea for Fire in the Blood in 1937. “New subjects and a novel,” she writes in her notebook. “I thought about The Young and the Old . .. The impossibility of understanding that ‘fire in the blood’. A good idea. Disadvantage: no clear characters.” It wasn’t until a visit to Issy-l’Evêque in 1938 that she stumbled across the ideal setting. “Everyone lives in his own house, on his own land, distrusts his neighbours, harvests his wheat, counts his money and doesn’t give a thought to the rest of the world,” says Sylvestre, the narrator of the novella.

Two pages of Fire in the Blood were found in the famous suitcase lined with green material and embossed with the letters LN, the initials of Némirovsky’s father. They were in the form of a manuscript typed by her husband; the rest had been entrusted, along with some short stories, to a close friend during the war. The complete novella was discovered in 2005 by Olivier Philipponnat and Patrick Lienhardt, who were researching a biography of Némirovsky that comes out in France this week. They found it among papers that Denise Epstein had donated to the Institut Mémoires de l’Edition Contemporaine – 30 pages of her mother’s neat, small handwriting. The beginning was the same as the two typed pages found in the suitcase.

Fire in the Blood is about the contrast between youth and old age, about the “fire in the blood” that rages when we’re young, and the gradual process of growing old and finding peace. It is also a brilliant portrayal of French paysan society: of the underlying cruelty, the secrets, the currents that motivate people and rule their deceptively simple lives. Némirovsky is as skilled as Chekhov at pinpointing an emotion or a gesture. Her observations are often brutally honest and always compelling. One of the characters, for example, has married a rich older man. She lies in bed, “dreaming of her lover, counting her husband’s sighs, wondering, ‘When will he finally stop breathing?’ ”.

Epstein, now 77, and living in Toulouse, describes it as a “lovely book. No war and no Jews, which is a good start”. Without the backdrop of wartime, when life is charged with tension, the book has a slower, less dramatic feel than Suite Française. But, after a languid start in the Burgundy countryside, the drama of the characters’ lives unfolds in a rush. It is thanks to Epstein that her mother’s work has survived to find acclaim. When the time came for the 13-year-old to flee from the French police, she had three things to take with her: her younger sister, the leather suitcase containing her mother’s notebooks, and her favourite doll. “As I had only two hands,” she recalls, “I took my sister and the suitcase. I often wonder what happened to that doll. I feel as if I’ve been searching for it ever since.”

The final work from Némirovsky’s suitcase is a collection of short stories; these will be published, according to Epstein, though not in the immediate future. It will mark the end of an unrivalled posthumous career for a woman who is surely one of the greatest writers of the 20th century.

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