Montgomery, Sir Frank Percival (‘Monty’) (1892–1972), rugby player and radiologist, was born 10 June 1892 at 3 Lower Crescent, Belfast, son of Henry Montgomery, presbyterian clergyman and moderator of the Presbyterian Church in Ireland in 1912, and Euphemia Anne Montgomery (née Goudy). Educated at Campbell College, Belfast, he played cricket and rugby for the school. His mother wanted him to become a clergyman like his father, but he convinced her to allow him to study medicine so that he could become a medical missionary, and entered QUB in 1910. At Queen's he played full-back on the university and Ulster provincial rugby teams, and on 14 February 1914 won his first cap at full-back for Ireland, when they were defeated 17–12 by England at Twickenham, in a game in which he was said to have ‘acquitted himself well’ (Ir. Times, 16 Feb. 1914). He was praised for his performance in Ireland's 6–0 defeat of Scotland on 28 February 1914: ‘It is now many years since a Lansdowne Road crowd saw a better exhibition of the full-back game by an Irishman than what young Montgomery showed us’ (Ir. Times, 2 Mar. 1914). His third and final Irish cap was won in an 11–3 defeat by Wales on 14 March 1914; in ‘the roughest international ever witnessed in Ireland’ (Ir. Times, 16 Mar. 1914), he continued to play despite being seriously injured. He was considered the Irish full-back of the future, especially noted for the effectiveness of his tackling, but his rugby career was cut short by the outbreak of war.
Graduating from QUB in 1915 with an MB, B.Ch., and BAO, he immediately joined the RAMC, served on the western front for the duration of the war, and was awarded the MC (1916) and the French Croix de Guerre (1917) with bar (1918). Having spent four years (1919–23) as a divisional inspector with the Egyptian department of public health in Cairo, he studied radiology in England, graduating from Cambridge with a diploma in medical radiology and electrology (1924). Returning to Belfast to practise as a consulting radiologist, he possessed the only radium then available in Northern Ireland, having invested his post-service gratuity in radium needles. In 1938 he was made a fellow of the faculty of radiologists. Elected to the visiting staff of the Ulster Hospital for Women and Children (1925) and the Royal Victoria Hospital, Belfast (1929), he was also a member of the health advisory council of Northern Ireland (1944–7), fellow of the British association of radiologists, first chairman of the Northern Ireland hospitals authority (1948–56), and honorary governor of the Ulster Hospital, Dundonald. A pioneer of radiotherapy in Northern Ireland, he was knighted for his service to medicine (1953), and in 1962 was made honorary fellow of the faculty of radiologists by the Royal College of Surgeons in Ireland.
President of the Ulster branch of the IRFU (1936–7), in 1957 he was captain of Royal County Down golf club. In 1932–3 he was president of the Old Campbellians. A member of the QUB senate (1942–67), he was also a pro-chancellor of the university (1956–67). He married (1925) Joan, elder daughter of W. Christopherson of Ipswich, Suffolk. They had two sons and two daughters and lived at 56 Osborne Park and ‘Foxhall’, 9 Broomhill Park, Belfast, where he died 11 August 1972. The Northern Ireland radiotherapy centre was named Montgomery House in his honour. His sister Eleanor was a presbyterian missionary in India.