He told me about all the enormities he had seen at the front - the mouthless mangled faces, the human ribs whence rats would steal, the frenzied tortured horses, with leg or quarter rent away, still living; the rotted farms, the dazed and hopeless peasants; his innumerable suffering comrades; the desert of no-man's-land; and all the thunder and moaning of war; and the reek and freezing of war; and the driving - the callous, perpetual driving by some great force which shovelled warm human hearts and bodies, warm human hopes, by the million into the furnace.

(a) The desire to suffer and to die - especially when suffering is associated with glory. (b) Fear of immunity from danger when our friends are suffering.

It always seemed to me then that I yielded to desire to join the W.A.A.C., a desire which my poorer contemporaries, who had to hurry through with their preparations to earn livings, could not afford to indulge in. I had been so infinitely happier both nursing and in the W.A.A.C. than I had been in that ghastly year at Oxford in 1917, that it never occurred to me that Army life was anything but a fortunate privilege.

I cannot describe it excepting that it was one of the most wonderful things I ever saw or heard in my life. There were fifteen thousand of us there, all in khaki. The band was splendid, and I wish you could have heard those 15,000 girls all singing 'Fight the Good Fight' with the rolling drums of the military band. The preacher was very good and very simple. Many of the girls were sobbing when he had finished.

I was sixteen when the war started. The first thing it made me do was fall in love. Brevity of life makes passion more insistent. The youngest and fittest in uniform. The erotic attraction of death.

Miss Holtby, my tutor told me, was anxious, like myself, to study the nineteenth century; she had also been down from college for a year serving in the W.A.A.C., so perhaps that too would form a link between us. Quite sure that it would not, and wishing that I could have had the Dean to myself, I sauntered lugubriously down to Hertford, where I was to meet this stranger towards whom I felt so unaccountably antagonistic.

I was staring gloomily at the Oxford engravings and photographs of the Dolomites which clustered together so companionably upon the Dean's study wall, when Winifred Holtby burst suddenly in upon the morose atmosphere of ruminant lethargy. Superbly tall, and vigorous as the young Diana with her long straight limbs and her golden hair, her vitality smote with the effect of a blow upon my jaded nerves. Only too aware that I had lost that youth and energy for ever, I found myself furiously resenting its possessor.

Hitherto, society has drawn one prime division between two sections of people, the line of sex-differentiation, with men above and women below. The Old Feminists believe that the conception of this line, and the attempt to preserve it by political and economic laws and social traditions not only checks the development of the woman's personality, but prevents her from making that contribution to the common good which is the privilege and the obligation of every human being.

While the inequality exists, while injustice is done and opportunities denied to the great majority of women, I shall have to be a feminist, and an Old Feminist, with the motto Equality First. And I shan't be happy till I get it.

She (Winifred Holtby) was tremendous fun and understood, better than any other grown-up, children's fantasies and fears. We had a dressing-up box full of discarded hats and dresses, scarves and masks and wooden necklaces from Africa. We would perform for our parents the plays Winifred wrote for us... I was a boisterous child, so Winifred, despite her frailty, joined in our rougher games as well. She would crawl around the nursery, balancing cushions on her back, while I rode on top, pretending to direct an elephant from my howdah.

There are today in England - and in France and Germany and Austria and Italy, one imagines - women peacefully married to men whom they respect, for whom they feel deep affection and whose children they have borne, who will yet turn heartsick and lose colour at the sight of a khaki-clad figure, a lean ghost from a lost age, a word, a memory. These are they whose youth was violently severed by war and death; a word on the telephone, a scribbled line on paper, and their future ceased. They have built up their lives again, but their safety is not absolute, their fortress not impregnable.

Friday 27th September, 1935: I told him that I thought Harry ought to tell Winifred he loved her and always had; that he'd like to marry her when she was better; and that only another man could put this over to him in such a way that he wouldn't be offended or frightened; and that it should be done at once, because, for all our renewed hopes, time might be short.

Saturday 28th September, 1935: At about three o'clock Hilda Reid rang up to say that Dr. Obermer had been round to the home and had already put Winifred under morphia; she was now unconscious and would never be permitted to come back to consciousness again.

Later I learnt that Dr. Obermer did this because after Harry had been with Winifred she was so happy and excited that he feared a violent convulsion for her, with physical pain and mental anguish; and that he thought it best to let her go out on that moment of happiness, with the cruel realization that what she was hoping could never be fulfilled.

The room was dim, with a shaded lamp, but I saw at once that Winifred had changed, and though her pulse was still tolerably strong, she was breathing very shallowly, and wore the look that I had so often seen on the faces of dying men in the War. Her lips were only slightly parted; her eyes were serenely closed and her hair brushed back from the forehead. She looked utterly at peace - "like a tired child", as Gordon said afterwards, "who has at last had a good night after many bad ones".

Shortly after six o'clock I realised that she was breathing more shallowly, while her pulse was slower and weaker. After almost a quarter of an hour her pulse, which I was holding, had almost stopped, and her breathing seemed to come from her throat only. I nodded to Gordon and he came and stood beside her. It was strange, incredible, after all the years of our friendship and all that we had shared together, to feel her life flickering out under my hand. Suddenly her pulse stopped; she had given two or three deeper breaths and then these ceased and I thought she had stopped breathing too; but after a moment came one final, lingering sigh, and then everything was at an end.

But when I came to consider local government, I began to see how it was in essence the first line defence thrown up by the community against our common enemies-poverty, sickness, ignorance, isolation, and social maladjustment. The battle is not faultlessly conducted, nor are the motives of those who take part in it all righteousness or disinterested. But the war, is, I believe worth fighting... we are not only single individuals, each face to face with eternity and our separate spirits; we are members one of another.

Spent most of the morning reading Vera Brittain on Winifred Holtby - frightfully bad, but it aroused various reflections. It is a glorification of the second-rate and sentimental and reeks of femininity. Why should woman on woman so painfully lack irony, humour or bite? And it's too winsome and noble, somehow. But much of that belongs to the First War, and not to women only. (There it is in Rupert Brooke.) A musty aroma of danger glamourized and not understood by girls at home floats out of this book. Vera Brittain writes of the number of women now happily married and with children who still hark back to a khaki ghost which stands for the most acute and upsetting feelings they have ever had in their lives. Which is true I think, and the worst of it is that the ghost is often almost entirely a creature of their imagination.

My parents, my brother and I, and my mother's dear friend Winifred Holtby lived in a long, thin house at 19 Glebe Place, Chelsea, a street much favoured by artists, actors and other Chelsea characters. John and I loved Auntie Winifred. Tall and blonde, she radiated a gaiety that helped to dispel the sadness in my mother's life. They had met at Somerville college, Oxford, and had sharedd flats in London. Both were regarded as progressive writers, addressing topics like feminism and equal rights not much discussed in conventional society.

Some critics and commentators have suggested that their relationship must have been a lesbian one. My mother deeply resented this. She felt that it was inspired by a subtle anti-feminism to the effect that women could never be real friends unless there was a sexual motivation, while the friendships of men had been celebrated in literature from classical times. My mother was instinctively heterosexual. But as a famous woman author holding progressive opinions, she became an icon to feminists and in particular to lesbian feminists. She sometimes took me with her when she met lesbian women who were besotted with her, to indicate her own commitment to marriage and family.

In the early period of their friendship, Holtby had rescued Brittain from grief at the loss during the war of her brother and her fiancé, Roland Leighton. After Holtby's death, Brittain attempted to repay the debt by ensuring, as her friend's literary executor, that her final and most significant work saw the light of day. The major obstacle she faced was the indomitable figure of Holtby's mother, Alice, the first woman alderman of the East Riding. She feared that her daughter's depiction of local government, allied to the vein of satire and "puckish mischief" familiar from her earlier books, might expose her own job to criticism and ridicule. Holtby had tried to allay these fears in a "Prefatory Letter" to her mother in which she admitted that while Mrs Holtby's descriptions had first alerted her to the drama of English local government, her material for the novel had emanated from sources "unknown to you".

This wasn't strictly true. Holtby had used council minutes taken from her mother's wastepaper basket to help plot her story. In 1932 she had attended the public inquiry into a land purchase scandal in Hull, which had led to the suicide of a long-serving Conservative member of the council, guilty of making profits from land sales. This case would provide the basis for the scheming of Alderman Snaith and Councillor Huggins in the novel. The real-life models for the book's locale are also clearly identifiable. Although the South Riding is a fictional place – there are only North, West and East Ridings, since "riding" comes from the Anglo-Saxon word "thriding", meaning a third – Holtby's novel is located in the East Riding she knew so well. Kingsport is instantly recognisable as Hull. Kiplington, the coastal town where Sarah Burton is headmistress, is an amalgam of Hornsea and Withernsea, the seaside towns where Holtby lodged while writing the book. The novel's Cold Harbour Colony, the ex-servicemen's colony of smallholdings, is based on Sunk Island, the area of Holderness that rose from the waters of the Humber, while Robert Carne's decaying Maythorpe Hall was inspired by the White Hall in Winestead, which Holtby would have observed, shuttered and derelict, as a passenger on the Hull-Withernsea railway...

Sarah Burton is the book's chief advocate for social change, and an optimistic believer in the eradication of disease, poverty and ignorance through greater governmental intervention in people's lives. She gets her "astonishing" red hair from the Labour MP Ellen Wilkinson, Holtby's colleague at Time and Tide, and as a headmistress she is reminiscent of Jean McWilliam, Holtby's friend from her wartime service in France with the WAACs, who later went to teach in Pretoria. But, most of all, Sarah is Holtby herself, never more so than when she is defending the right of single women to lead fruitful, independent lives. "I was born to be a spinster," Sarah tells herself, "and by God, I'm going to spin."

Burton puts her trust in the power of collective action by local government to create a more beneficent "English landscape". As she explains to Alderman Mrs Beddows (whose "racy tongue" was borrowed from Holtby's mother): "If the growth of civilisation means anything, it means the gradual reduction of the areas ruled by chance – Providence, if you like." Yet the novel recognises that chance still has a hand to play. Lydia Holly, the talented girl from the slum dwellings known as the Shacks, is rescued from the domestic dead-end of caring for her younger siblings not by Burton's efforts, but by Mr Holly's remarriage, which frees Lydia to return to school. And it is chance that makes progressive, idealistic Burton fall in love with the local squire Robert Carne, a symbolic figure of reaction, who opposes the expansion of local government and the widespread benefits it would bring.