Thornton, Brigid Lyons (1896–1987), public health doctor and first female commissioned officer in the Irish Free State army, was born 13 May 1896 in Northyard, Scramogue, Co. Roscommon, the eldest child of the two daughters and one son of Patrick Lyons, farmer, and Margaret Lyons (née McGuiness), of a staunchly republican family. Her father was a Fenian who had been active in the land wars of the 1880s, and spent some time in Sligo jail. Her mother died at the birth of the youngest child, and at the age of eight Brigid went to Longford to live with her uncle Frank McGuiness (1868–1934) and his wife, Kate, who were childless. They were keen to support and educate their bright young niece, who thereafter made only short visits to her father and siblings. Educated first at North Yard national school, then at the Convent of Mercy, Longford, and the Ursuline Convent, Sligo, Brigid entered UCG in 1915 to study medicine.
Frank McGuiness was an ardent republican who later became close to Arthur Griffith (qv) and W. T. Cosgrave (qv) in Reading jail, served as chairman of Longford county council, and was later elected to the dáil and the seanad. He had a strong influence on Brigid and she joined Cumann na mBan while still a teenager. On Easter Monday 1916, while she was at home in Longford, news that the Irish Volunteers had staged a rebellion in Dublin reached her and her family. With an uncle and some friends she travelled to Dublin the next day, eventually joining another uncle, Joe McGuinness (qv), at the Four Courts. There she and other women made tea and sandwiches and tended to the wounded, though she found her minimal medical training was insufficient preparation. When the order to surrender came the following Saturday, she described the silence that descended on the city as ‘louder than all the noise’ (Griffith and O'Grady, 74); for her it was a ‘terrible, shattering, chaotic moment’ (ibid., 75). They were kept overnight in the Four Courts, and a priest from nearby Church Street ‘lambasted us with abuse all night for doing what we did’ (ibid., 77). Brigid and the other women were transferred first to the barracks at Richmond Street and then to Kilmainham jail. During their transfer, the open hostility of the local women, many of whom had husbands fighting in France, terrified and surprised her. From her cell she heard the executions of the leaders of the rebellion, and the horror of the sound of the dawn volleys stayed with her all her life.
After her early release from jail Brigid continued her medical studies and her republican activities, disrupting British army recruitment drives, destroying recruitment posters around Galway city, and organising fund-raisers for the families of the men imprisoned after the rebellion. During the war of independence she rose to the rank of commandant, and her deeds included an incident in December 1920, when she smuggled hand-grenades by train to the Longford brigade of the IRA under the command of Seán Mac Eoin (qv). Later, when he was captured and held at the King George V (later St Bricin's) Hospital, and subsequently in Mountjoy, she carried messages to Michael Collins (qv) from Mac Eoin. She obtained intelligence information for a daring, but unsuccessful, attempt to release him. Though she had reservations about the Anglo–Irish treaty of December 1921, she sided strongly with Collins in supporting it.
Amid all the excitement of her political activities, Brigid managed to complete her studies, and she graduated MB, B.Ch., in 1922. Collins offered her a commission in the newly formed Irish national army, which she accepted; she was the only female officer commissioned in the Irish army until 1981. As a first lieutenant in the army medical service (1922–4) under the directorship of Major General Maurice Hayes (1878–1930), one of her first duties was care of the anti-treatyite prisoners in Kilmainham jail. This brought her into contact with many of her former colleagues, which she found distressing. For fifteen months she was based in St Bricin's, where part of her work was planning a new administrative direction for the hospital and helping form the nursing corps and a team of medical orderlies. At this time she also began an interest in public health and paediatric medicine. She suffered a recurrence of a childhood illness, tuberculosis, and a serious operation to treat her left her almost totally incapacitated. She was advised to travel to Nice in southern France for her recuperation, and spent her time there walking and helping other patients. It was in Nice that she met her future husband, Captain Edward Thornton (b. 1899) from Co. Mayo, also convalescing from tuberculosis.
Brigid moved to Lysin Fedey, Switzerland, and spent a year under a new treatment regime. Taking advantage of her situation, she studied several aspects of tuberculosis and attended medical lectures. Edward Thornton joined her in Lysin for his convalescence and they continued their romance, returning to Ireland to marry on 10 October 1925. While he resumed his medical care in Switzerland, she obtained a diploma in public health from the NUI (1927). Edward returned to Ireland and qualified at the bar and later worked as a solicitor, but he spent winters convalescing in Switzerland until 1932. Having left the army, Brigid spent the year 1928 as temporary medical officer in Co. Kildare, with responsibility for tuberculosis, and as assistant medical officer of health for Co. Cork, before being appointed in 1929 assistant medical officer of health and school medical officer for Dublin county borough, based at the Carnegie welfare centre in Lord Edward Street, Dublin. She worked there until her retirement. Specialising in paediatrics, and aware of the pioneering work of Dorothy Price (qv), she was involved in the early BCG vaccination schemes and helped to eradicate many of the diseases, such as tuberculosis, which affected the children of Dublin.
Throughout her life Brigid Thornton fought for the underprivileged, believing strongly that women had an important contribution to make in many occupations traditionally dominated by men. Injustice and deprivation moved her, and she used her energy to fight for the rights of political prisoners, for Belgian refugees, and for the right of women to vote. There were no children from her marriage and her husband died suddenly on 19 July 1947. Following her retirement, Brigid continued to undertake voluntary medical work (including in the library) at the Rotunda Hospital, crossing town from her apartment on Fitzwilliam Place. She kept abreast of the latest medical developments and remained an active member of several charitable organisations. Devoted to the Medical Benevolent Fund, she was also secretary to the public health section of the Royal Academy of Medicine. By the late 1970s she was partially blind and unable to travel very far. She died, aged ninety-one, in April 1987 and was buried in Toormore cemetery, Foxford, Co. Mayo, beside her husband. A guard of honour from the western command fired a graveside salute.