This trait she believed she had inherited from her mother's family, the Pearsall Smiths, immensely rich Philadelphia Quakers. Two generations earlier they had moved to England in 1899, settling in a big house in Surrey, to carry out their mission of revivalism and social reform. High up on the agenda was female emancipation, for, despite the fact that the most celebrated of their number was Barbara's uncle Logan Pearsall Smith (who published his collections of Trivia and who had employed both Kenneth Clark and Cyril Connolly as secretaries), the family was a strict matriarchy. Barbara once told me, "All the Pearsall Smith women were monsters, and I'm one too."
Her father, Oliver Strachey, one of Lytton's elder brothers, was an ace cryptographer during both world wars. Her mother, Ray, was his second wife. (The daughter of his first marriage, Barbara's half-sister, was the writer Julia Strachey.) As little girls, Ray Costelloe and her sister Karin (who married Virginia Woolf's brother, the analyst Adrian Stephen) were abandoned by their mother, Mary, who left her first husband and children to live with Bernard Berenson at Villa I Tatti, near Florence. Barbara was largely brought up by her aunt Alys Pearsall Smith, who never stopped loving the husband who had unceremoniously dumped her - Bertrand Russell.
Many of these famous friends and relations were painted by Ray, who took up painting as a hobby late in life. (Some of her Bloomsbury portraits are on view temporarily at the National Portrait Gallery.) When I first met Barbara, she was living in a large house in Kensington that had a long room, empty of furniture, with these pictures lining the walls.
She was then retiring from her job at the BBC, where she had been central to the metamorphosis of the General Overseas Service into the World Service in 1965. Barbara had had a great deal to do with making the fairly rudimentary foreign broadcasting service, which relied heavily on repeats of domestic broadcasts, into a 24-hour English broadcasting service. She was very good at the details of programming on different frequencies to audiences in different time zones.
Barbara Strachey was at school in Switzerland and was then sent to Oxford High School and to Vienna before Oxford, where she took a disappointing Third in history. In an attempt to end her youthful rebellion, her parents sent her on a windjammer journey to Australia. She rebelled even further, by marrying a fellow passenger, Olaf Hultin, the son of Professor Arvid Hultin of Helsingfors. They married in January 1934, had a son, Roger, in October and divorced three years later in 1937.
In September of that year she married Wolf Halpern, son of Dr George Halpern of Jerusalem. (Barbara was pleased to have enlarged her ethnic horizons. She was a keen amateur ethnographer, and boasted, after a stay in hospital where several of the nurses were of West African origin, that she could guess their national tribal affiliations with 100 per cent accuracy.) Halpern joined the RAF and died in action in 1943. Barbara used his name until she began her second career as an author.
Following the untimely death in 1975 of her brother Christopher, who was Oxford's first professor of computing, Barbara moved into a small house in Jericho. There she managed to pursue a passion for gardening in a truly tiny space at the back. The house had a lot of stairs. In a room in the basement were stacks of filing cupboards, which contained the 20,000 letters and manuscripts that had devolved upon her from her grandmother, aunts and mother, each of whom wrote a daily letter to the others. Eventually she lodged Alys's large correspondence (which included some self-incriminating letters from Russell about his relationship with G.E. Moore, about whom I was writing a book, and which she gleefully produced for me, as she disapproved of "Bertie") with the great Russell collection at McMaster University in Canada.
These papers contained most of the sources she needed to write her first book, Remarkable Relations (1980), the story of the Pearsall Smith family. She was a fine writer, and the material was superlative, resulting in a book that received much critical praise.
This gave her the confidence to seek a publisher for a project she had been working on for a very long time. Barbara's daily routine included polishing off the Times crossword in a very few minutes, and working on her maps of Frodo's journeys in Middle Earth. Though she had no training in cartography, she drew the maps herself for Journeys of Frodo (1981), an atlas of J.R.R. Tolkien's The Lord of the Rings, to which she was devoted. To Tolkien adepts she is one of the immortals.
Next she did a book that she particularly enjoyed, because it gave her a reason to visit I Tatti, Mary Berenson: a self-portrait from her letters and diaries (1983), which she edited with Jayne Samuels. Then in 1985 she did a partial history of the other half of her own family: The Strachey Line: an English family in America, in India and at home, 1570 to 1902.
Despite her forbidding demeanour, Barbara Strachey enjoyed entertaining, and was a meticulous hostess. I remember a lunch in Jericho with Lady Ottoline Morrell's daughter, Julian, and her husband Igor Vinogradoff. The food and, especially, the wine were good. Barbara was an unlikely bon vivant, but she used to relish her excursions with the Sunday Times Wine Club. She was a great traveller while her health allowed, even travelling overland to India by bus - and her house was filled with tribal art souvenirs of her journeys to distant places.
Even when she had lost some mobility, she was energetic. To mark her 80th birthday in 1992 she hired a boat and took her guests on the river around Oxford. Before she had to leave her house with its impossible stairs, she used to navigate Oxford in a 4mph electric cart. She loved going to the opera, and was proud of belonging to the Cranium Club, a dining club that numbers many descendants of the Bloomsbury group among its members.
Barbara Strachey was formidable rather than likeable, and it has to be admitted that she was a difficult woman. But she had the resources of character of both sides of her remarkable families. Though she inspired nervousness rather than tenderness, it was difficult not to feel a fondness for her.
Barbara Strachey, broadcaster and writer: born 17 July 1912; married 1934 Olaf Hultin (one son; marriage dissolved 1937), 1937 Wolf Halpern (died 1943); died Oxford 15 October 1999.