But the biography, out this month, will claim that the Leeds-born novelist had no idea her family's true history had parallels with the rags to riches tale of Woman of Substance star, Emma Harte.
North Yorkshire-based writer Piers Dudgeon, discovere
d that the 71-year-old's mother, Freda, was an illegitimate child born to an Edwardian Yorkshire servant, Edith, who is believed to have had an affair with a wealthier, married man who left her impoverished.
Fictional heroine Emma Harte also starts out as a maid in a wealthy Yorkshire household, until she is seduced by her master, Edwin Fairley, who finally abandons her after she has given birth to a daughter.
The book claims, however, that the novelist did not even know her mother was born out of wedlock.
It suggests that Freda's well documented zeal for her daughter to succeed must have been driven by the hardship she experienced as a child, when she was sent to a Ripon workhouse and her siblings shipped abroad by Dr Barnardo's.
Mr Dudgeon, who is based in Sawdon, near York, carried out research in Leeds, Ripon and the Dales
He said: "Barbara told me very little about her mother and grandmother before I began writing this book... at the end, when I showed her the manuscript, her shock confirmed that she had not known, and she found it very difficult to accept that she had written about these things of which she had no conscious knowledge."
In an interview with the Yorkshire Post more than 10 years ago, Mrs Taylor Bradford claimed Emma Harte was based on herself.
In 1994, she said: "It's only now I realise that Emma Harte is, in fact, me.
"I wasn't a maid and didn't have a child. But her canny tough Yorkshire grit is totally me. Friends probably suspected as much years ago."
The biography tracks the glittering career of Mrs Taylor Bradford who began as a typist on the Yorkshire Evening Post newspaper in Leeds
She now lives in New York and has sold 75 million copies of her books.
The Life and Work of Barbara Taylor Bradford will be available from February 21.
