A Times writer has been shortlisted for a leading literary prize for a book that started out as a letter to his mother.

When Sathnam Sanghera wanted to explain to his parents why he did not want an arranged marriage he started digging into the history of his Sikh immigrant family to preempt the complaint from his mother that “you wouldn’t do this if you knew what I had been through”.

The letter turned into If You Don’t Know Me by Now: A Memoir of Love, Secrets and Lies in Wolverhampton after “someone in publishing told me it would be a good way to solve my many problems”, Sanghera, 32, said last night. “It worked.”

It is one of four books in contention for the Biography prize at the Costa Book Awards, formerly known as the Whitbread Book Awards.

His rivals are two other current journalists (Judith Mackrell, for her biography of the ballerina Lydia Lopokova, and Jackie Wullschlager, for her book on the artist Marc Chagall) and a nonagenarian former publisher who worked for the BBC during the Second World War, Diana Athill, for her fifth volume of the memoir Somewhere Towards the End.

Biography is one of five categories, along with first novel, novel, poetry and children’s book, in an award established in 1971 to recognise the “most enjoyable” books by writers based in Britain and Ireland.

Other nominees include Louis de Bernières, author of Captain Corelli’s Mandolin, for the novel A Partisan’s Daughter, and Michelle Magorian for the children’s book Just Henry.

The judges said that Sanghera’s work was: “Quietly witty, engrossing and tragicomic – this insight into parallel culture in Britain today is the poignant story of an exceptional family that everyone should read.”

Sanghera ended up leaving his job at the Financial Times and was forced to lay his emotions harrowingly bare. “The whole thing was a massive panic attack,” he said. “The book was a way for me to tell my parents that I didn’t want to have an arranged marriage. I’m from a very traditonal Sikh family: I’ve got 54 first cousins, none of whom defied convention and married out. I was under a lot of pressure so I thought I would write my Mum a letter. That letter turned into a book.” Sanghera set out to learn more about his parents’ past so that he could better understand their likely objections. What he found was “a family history much darker than I had realised: domestic violence, mental illness. It completely threw me.”

However, he said that the book was emphatically not part of the current glut of misery memoirs. “I had a really happy childhood because I didn’t really get what was going on around me. It’s meant to be funny,” he said.

The book addresses the harsh life of Sanghera’s father in rural Punjab, his mother’s formidable resilience raising her family in a country where she did not speak the language and, most of all, the author’s anguished conflict between the family that he left behind in the Midlands and his highflying career and Westernised lifestyle in London.

Mercifully, there has been a happy ending. “My Mum can’t read English but she knows what’s in the book and she’s chuffed,” he said. “It’s her story and she wanted it told. She doesn’t know about the nomination yet though – some things are really hard to explain in Punjabi.”

Full list of nominees:

COSTA BOOK AWARDS 2008 SHORTLISTS

2008 Costa Novel Award shortlist

Sebastian Barry for The Secret Scripture (Faber and Faber)

Chris Cleave for The Other Hand (Sceptre)

Louis de Bernières for A Partisan’s Daughter (Harvill Secker)

Patrick McGrath for Trauma (Bloomsbury)

2008 Costa First Novel Award shortlist

Poppy Adams for The Behaviour of Moths (Virago)

Sadie Jones for The Outcast (Chatto & Windus)

Jennie Rooney for Inside the Whale (Chatto & Windus)

Tom Rob Smith for Child 44 (Simon & Schuster)

2008 Costa Biography Award shortlist

Diana Athill for Somewhere Towards the End (Granta)

Judith Mackrell for Bloomsbury Ballerina (Weidenfeld & Nicolson)

Sathnam Sanghera for If You Don’t Know Me By Now (Viking)

Jackie Wullschlager for Chagall (Allen Lane)

2008 Costa Poetry Award shortlist

Ciaran Carson for For All We Know (Gallery Books)

Adam Foulds for The Broken Word (Jonathan Cape)

Kathryn Simmonds for Sunday at the Skin Launderette (Seren)

Greta Stoddart for Salvation Jane (Anvil Press)

2008 Costa Children’s Book Award shortlist

Keith Gray for Ostrich Boys (Definitions)

Saci Lloyd for The Carbon Diaries 2015 (Hodder Children’s Books)

Michelle Magorian for Just Henry (Egmont Press)

Jenny Valentine for Broken Soup (HarperCollins Children’s Books)

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