Johnson [née Todd], Bertha Jane (1846–1927), promoter of women's higher education, was born at 3 New Street, Charing Cross, London, on 20 January 1846, the third of four children of the Irish physician Robert Bentley Todd FRS (1809–1860), professor of physiology at King's College, London, and his wife, Elizabeth Hart. Dr Todd was a pioneering advocate of nursing education and it was a home 'where there was very much the tradition of equal advantages and opportunities for girls and boys, men and women' (The Ship, December 1921, 35). The two elder girls were the first pupils at Elizabeth Sewell's school on the Isle of Wight, but Bertha was educated at home, sharing a tutor and drill lessons with her younger brother James before he went to Eton College. Her own talents were in the arts. Taught by a musical aunt, she became an accomplished pianist. She was among the early women students at the Slade School of Art and several of her paintings were exhibited at the Royal Academy.

On 16 April 1873 Bertha Todd married an Eton contemporary of James's, the Revd Arthur Henry Johnson (1845–1927), the second son of Captain George John Johnson of the Grenadier Guards. Johnson, now chaplain of All Souls College and, over the years, lecturer in modern history at several Oxford colleges, was a keen sportsman, naturalist, and gardener—once described as a 'country gentleman in Holy Orders' (Goldman, 33). He shared with Bertha qualities of vitality and charm and a gift for friendship and hospitality that gave them a prominent place in university society.

The introduction of women students into an ancient residential university, already pioneered at Cambridge by Henry Sidgwick and Emily Davies, was a challenge that appealed to the 'young married Oxford' of the 1870s. The birth of the Johnsons' two sons, Robert Arthur and George Wilfrid, did not prevent Bertha from serving on the committees that ran lecture courses for ladies from 1874, setting up the more ambitious Association for Promoting the Higher Education of Women in Oxford (AEW) in 1878, and founding the Anglican hostel Lady Margaret Hall, which opened, together with the undenominational Somerville Hall, in 1879. The success of these women's societies, not formally recognized by the university until 1910, depended on voluntary support from dons and their wives. Assisted by her husband, who delivered the first lecture in the series of 1874 and tutored women students until 1922, Bertha Johnson made it her life's work. She was secretary to Lady Margaret Hall from 1880 to 1914, and at first in effect domestic bursar, overseeing the economical running of the household. As lady secretary to the AEW (1883–94) she organized tuition for rapidly growing numbers of women students, and supervised those who were not attached to a hall but lived at home or with ‘hostesses’ in the city. Her encouragement also played a part in the success of two further Anglican women's halls, St Hugh's, opened in 1886 by Elizabeth Wordsworth, and St Hilda's, founded by Dorothea Beale in 1893. But the welfare of ‘home students’, as they were known after 1889, became her particular concern. In 1894 she was appointed by the AEW as their principal. In 1910, when a delegacy for women students was set up and home students came under the control of the university, she became as principal of the Society of Oxford Home-Students (SOHS) the first woman with a senior university appointment. She held this post—always, at her own insistence, without payment—until she retired at seventy-five in 1921. In 1920, when women were admitted to membership of the university, she was the first of the five women principals to receive the MA by decree.

Mrs Johnson came to be regarded as a conservative figure in the movement for women's education even by many Oxford friends and admirers. A unionist in her politics and a lifelong devotee of the fashions of the 1870s—Liberty gowns and William Morris wallpapers—she could be tenacious in resisting changes to the regime adopted in the early days for women students. She attached importance to careful chaperonage, and to the AEW's role in arranging the teaching of women by men dons; she thought women should follow courses specially devised for the individual rather than the curriculum of the male undergraduates. Her resignation as the AEW's lady secretary in 1894 was the outcome of a clash with the council and principal of Somerville, who challenged her control of tuition arrangements as the hall developed into a college with its own staff of women tutors. With her husband she became in 1895–6 an influential opponent of a bid to secure the admission of women to the Oxford BA degree. In this debate there were arguments that appealed to other supporters of the AEW (and to Henry and Eleanor Sidgwick at Cambridge) against subjecting women to the rigid requirements of the degree course, including compulsory Latin and Greek. But in 1897 Mrs Johnson was the only woman educationist to support a proposal—made by opponents of degrees for women at Oxford and Cambridge and viewed with dismay by the established women's societies—for a separate degree-awarding university for women. Speaking as the mother of two undergraduate sons (Robert was president of the Oxford Union in 1897), she defended this scheme above all on the grounds that even well-wishers of women's higher education opposed the idea of co-education.

University men are not willing that women should share fully in the life of the Universities. … It may be right or it may be wrong, but the fact remains that we are no more liked now than when we began … [To] bring highly educated girls into disfavour with the majority of highly educated young men, may be found to be a dangerous thing for our nation.

University Degrees for Women: Report of a Conference Convened by the Governors of Royal Holloway College, 4 Dec 1897, 52–3, Bertha Johnson MSS

Bertha Johnson was not among the Oxford women who followed Mrs Humphry Ward in opposing women's suffrage—in 1894 she chaired a drawing-room meeting in support of a suffrage petition—and family pressures evidently helped to shape her views on the place of women in Oxford. But she was no egalitarian—'The imitation of men by women has always seemed to me to be a poor thing' (speech to women students' debating society, 1 Dec 1895, Bertha Johnson MSS). Nor was she much moved by the argument that an Oxford degree would be valuable to the professional woman. Her own career exemplified instead the opportunities that opened within the voluntary sector to upper-middle-class women of her generation. She became Headington's first woman poor-law guardian, president of the Oxford Working Women's Provident Society, and vice-president of the Oxford Charity Organization Society committee, and was an active and sympathetic workhouse and district visitor until the end of her life. She also served (1903–22) as a co-opted member of Oxfordshire county council's education committee. The SOHS was run from the Johnsons' comfortable and attractive home—first at 8 Merton Street, then at 5 South Parks Road—and her defence of the home student was always based on the conviction that there were 'considerations that make home life, even when the home is not our own, better for young women than College life' (The Ship, December 1921, 19).

By the early twentieth century, the SOHS was a diverse and growing society which included mature students, Roman Catholics based in a hostel run by nuns at Cherwell Edge, and increasing numbers of foreigners. The home students—seen by some critics as a threat to the university's policy of discouraging social contacts between male undergraduates and women, and by others as missing out on the college experience—gained some protection from Bertha Johnson's quietly autocratic regime, and appreciated her warm interest in individual students, past and present. The SOHS acquired its own common room in Ship Street (bought and presented by Arthur Johnson), and adopted as its motto that of Mrs Johnson's family, Faire sans dire. Twenty-five years after her death the society became Oxford's fifth women's college: St Anne's.

Despite Arthur Johnson's loyal support for her work, it cannot be assumed that there were no family tensions. Annie Rogers, the AEW's lady secretary from 1894, commented privately, 'If Mrs Johnson had been only a gentle and amiable person, I don't think she could ever have held her own against Mr. Johnson who was not very sympathetic with women's education' (Rogers to Butler, 27 Aug 1927, Rogers MSS). This fair, bespectacled woman with striking features and presence, fought her battles in middle life with 'a bit of temper', and remained formidable to the last. 'Her direct look, the power in her voice, the calm of her manner, her stately erect bearing were but the outward signs of a character of unnatural strength and self control' (Oxford Chronicle, 6 May 1927, 3). 'With all her simplicity and friendliness', wrote her obituarist in the Oxford Magazine, she had yet something of the 'great lady' (12 May 1927, 475). There were grandchildren, and her sons achieved professional success: Robert was knighted as deputy master of the Royal Mint and George became headmaster of Alleyne's School, Stevenage. But an obituarist claimed that in old age 'nothing gave her more pleasure than reminiscences of the old students' (Oxford Chronicle, 6 May 1927, 3). Bertha Johnson died of influenza at home in South Parks Road, Oxford, on 24 April 1927, less than three months after the death of her husband on 31 January, and was buried on 27 April with him in Holywell cemetery.