O'Brien (Arnold-Forster), Florence Mary (1854–1936), diarist, philanthropist, and craftswoman, was born 3 July 1854 in Bayswater, London, the second of four children of William Delafield Arnold and Frances Anne Arnold (née Hodgson). Her father, a son of Dr Thomas Arnold of Rugby and brother of the poet Matthew Arnold, had joined the Indian army in 1850, but later secured a civil appointment, becoming director of public instruction in Punjab in 1856. Following the death of his wife in India in March 1858 Arnold sent his children back to England by ship (January 1859), and, with a view to joining them in England, himself started on the return trip overland. However, during the journey he became seriously ill and he died at Gibraltar on 9 April 1859. The vacuum left by their parents' deaths was immediately filled by their aunt Jane (née Arnold) and William Edward Forster (qv), with whom Florence and her siblings developed a remarkably close relationship. The strength of their attachment is reflected in the children's decision formally to assume the name Arnold-Forster when the youngest sister, Frances, came of age in 1878.
Highly intelligent, sociable, accomplished, and well informed, as a young woman Florence was a keen letter-writer, diarist, and artist; since the age of fourteen she had travelled widely with her stepfather on the continent. She was also deeply interested in politics, both in Britain, where she closely followed the fortunes of the liberal party, and continental Europe. Following a visit to Budapest in 1876 she researched, and eventually wrote a biography of, the Hungarian patriot and statesman Ferenc Deák, which was published anonymously in 1881, and at once translated into Hungarian (1881).
Florence first visited Ireland on holiday in 1878; she returned in May 1880 during her stepuncle's first official visit as chief secretary for Ireland. Throughout the two years of his appointment she spent much of her time in Dublin, where she met and helped to entertain a varied political and social circle. She kept abreast of the rapidly changing political developments in Ireland and, as is evident from her journals, developed a deep mistrust of both the Land League and Irish nationalism. She made a permanent return to Ireland after her marriage (10 July 1883) to Robert (Robin) Vere O'Brien (d. 1913) of Old Church, near Limerick, with whom she had two sons and two daughters. Her husband was clerk of the peace at Ennis courthouse and an agent to the Inchiquin and de Vere estates.
Determined to put her practical and artistic talents to good use in her new home, Florence O'Brien quickly realised that she could benefit the local community by supporting the dwindling Limerick lace industry. She contacted lace craftswomen and provided them with top-quality materials and a range of her own designs, and organised the sale of their work, particularly among her circle of friends in Dublin and London. Supported by Alan Cole of the Department of Science and Art, South Kensington, London, and James Brenan RHA of the Crawford Municipal School of Art in Cork, she played a central role in the establishment of the Private Committee for Promoting Irish Lace, which founded the lace training school in Limerick in May 1889. At the committee's request she took over the direct running of the school in November 1893. Having moved with her family to New Hall, near Ennis, Co. Clare, in 1890, she went on to establish another craft industry, Clare Embroidery, from her home in 1895. Assisted by the O'Briens' children's nurse, a Scotswoman named Mina Keppie, the enterprise initially trained up to fifteen girls at a time; it was maintained after the family's move to nearby Ballyalla (1898), from where by 1910 up to twenty-seven girls at a time were receiving instruction. Central to the success of both ventures was the popularity of their products at arts and crafts exhibitions in Ireland, Britain, and America from the 1890s to the 1920s, notably those of the RDS, the Arts and Crafts Society of Ireland from its inception in 1896, Lady Arran's Windsor sale (1900), where examples of their work were purchased by both Queen Victoria and the princess of Wales, the world fairs in Chicago (1893) and St Louis (1904), at which they won several awards, and the Ideal Home exhibition in London (1908).
Besides her interest in craftwork, O'Brien was closely associated with developing health care in the Clare area. A member of the Women's National Health Association founded by Lady Aberdeen (qv), she was prominently involved in the establishment of a sanitorium at Ballyalla in 1912. She also started the Ennis District Nursing Association and for many years was directly responsible for the maintenance of the local district nurse. Throughout the war years and afterwards she assisted ex-servicemen in Clare through her association with the War Pensions Committee. During this time the lace industry went into decline, leading to the closure of the school in 1922; however, Clare Embroidery was still in production up to the time of Florence O'Brien's death at Ballyalla on 8 July 1936.