No one who is seriously interested in Jane Austen can learn much about her without turning to the work of Deirdre Le Faye, who has died aged 86. Described by the literary biographer Claire Harman as the “acknowledged super-authority” on Austen, Le Faye edited the novelist’s letters (1995), compiled a chronology about her that runs to almost 800 pages (2006), and prolifically produced further books and articles about Austen and her family.

All this work was based on meticulous archival research. Her achievement, according to Harman, was to provide an “unrivalled factual base” for Austen studies, a source of definitive information as little marred by ungrounded interpretation as possible. To her fellow Janeites, professional or otherwise, she offered a stern warning: interpretation was to be undertaken warily.

In print, at least. For Le Faye was also a scholar who could divulge a fantastic piece of Austen family gossip with the comment: “Miaowww!” She was generous in sharing information with fellow enthusiasts – gossip and dubious speculations included. Such things were to be weighted and judged along with everything else; but it was the facts, preferably facts as “crisp as lettuce leaves”, that were to be published.

This spirit of discernment is epitomised in her first book, Jane Austen: A Family Record (1989), which expands vastly on Jane Austen: Her Life and Letters: A Family Record (1913), written by two descendants of Austen’s nephew James Edward Austen-Leigh. That Le Faye was licensed by the family to do this made her, in effect, the authorised biographer of a long-dead author.

There was still much to be placed on the record, despite Austen’s ever-increasing popularity. For her updating of the Family Record, Le Faye drew on all kinds of unpublished (and widely scattered) material, ranging from letters and diaries to parish records and naval log-books. She located family gravestones and followed Austen’s footsteps across the south of England. The card index she made to marshal her discoveries ran to some 10,000 entries.

Le Faye mapped Austen’s world down to its minutiae, as is evident from her Chronology. This is the place to learn that Austen had a cold on Wednesday 9 March 1814, or that, two days later, at Godmersham, Kent, where her brother Edward lived, the snow was “deepish”. It is also the place to discover that in July 1813, as Austen was probably finishing Mansfield Park (Le Faye’s favourite of the novels), her authorship was still a relatively well-kept secret even within the family; and that in September 1817, some weeks after Austen’s death, her publisher John Murray thought it worthwhile to inform Lord Byron that he was going to publish two new novels by “the ingenious Author of Pride & Prejudice”. What readers might separate into trivia and events of greater significance emerge here side by side.

Such things mattered to Austen aficionados. As Le Faye noted at the time of her Family Record, there had been little original research along these lines since RW Chapman had produced his edition of Austen’s Letters in 1932. She was keenly aware that the novelist was still something of a mystery. Of an estimated 3,000 letters written by Austen, for example, only 161 survive. So the minutiae were arguably worth preserving, at the same time as wilder claims were to be guarded against.

This attitude led Le Faye to resist the identification of a young Austen as the sitter in the so-called Rice Portrait, the subject of a convoluted squabble in which she participated fiercely. (Sending a cartoon postcard of Wind in the Willows to a contact at the National Portrait Gallery, she wrote: “I find the Toad family portraits more convincing!”) Nonetheless, in 2010, after 40 years of Austen research and several revisions of her work, Le Faye could still argue that there was more research to be done and maybe further discoveries to be made. For 23 of those years, Le Faye had a day job, as an administrator in the British Museum’s department of medieval and later antiquities.

She was born in Bournemouth, to Leslie Smith, a retired army officer, and his wife, Anne Marie (nee Lucovich). The family moved to Farnborough and then Reading, where Deirdre attended the Abbey school after winning a scholarship. (The school had been renamed in honour of the forerunner Austen herself had attended briefly in the 1780s, and used as model for Mrs Goddard’s “real, honest, old-fashioned boarding-school” in Emma.) .

Deirdre left school after her father died, not long before she turned 16, and her mother found her a scholarship intended to “apprentice virtuous girls to a virtuous trade”, enabling her to train as a secretary. In 1952 Anne-Marie changed her name by deed poll to Le Faye, adopting a version of her mother’s maiden name (with the idea that it might help the law career of Deirdre’s older brother Kenneth), and her daughter followed suit.

Le Faye took various administrative jobs in London before joining the British Museum in 1975. At that time Austen was less of an interest for her than local history, and joining in archaeological digs, she discovered, meant cheap holidays in the countryside. (Likewise, she later wrote, Austen research meant “neatly combining literary detection with cheerful holidays” in “many attractive places in the south of England”.) Her interests were broad. She studied palaeography and the history of child rearing, basket-weaving and clay pipes unearthed during roadworks outside her office.

In the 1970s, as a member of the Camden History Society, she stumbled across the record of Austen’s aunt Philadelphia Hancock, buried in the churchyard of St John-at-Hampstead, alongside her daughter Eliza de Feuillide and Eliza’s son, Hastings. This discovery led to the further one about how little work had been done on the Austen family, and she made the acquaintance of the family’s heirs in Winchester. For five years, she was a regular visitor to the city, permitted to borrow items from the archives in the attic, take them back to London and Xerox them at the British Museum. From this work grew her Family Record.

Aside from producing her own books and articles, Le Faye was a member of the editorial board for Cambridge University Press’s eight-volume edition of Jane Austen’s Works (2005-08) and a patron of the library at Chawton House in Hampshire (another Austen family home), to which she bequeathed her own papers. The University of Southampton awarded her a DLitt in 2011, and she received the Benson medal from the Royal Society of Literature in 2014.

Diagnosed with motor neurone disease, Le Faye continued to work on Austen, preparing a fifth edition of the Letters for publication, and signing off emails “Austenian Love and Freindship for ever”.

Kenneth died in 2001.

• Deirdre Le Faye (Deirdre Gillian Gina Smith), literary scholar, born 26 October 1933; died 16 August 2020

• This article was amended on 14 October 2020. John Murray wrote to Lord Byron about new novels by Jane Austen in September 1817, rather than September 1819.