Ó Broin, León (1902–90), senior civil servant, historian, and author, was born Leo Byrne on 10 November 1902 at 21 Aungier Street, Dublin, the second of four sons of James P. Byrne, a potato factor's bookkeeper, and Mary Byrne (née Killeen), daughter of a seaman who abandoned his family. After early education in convent school, he attended Synge St. CBS (1915–18), where he was especially adept at languages. After working in several minor clerical employments, he became a clerk in the Kingsbridge headquarters of the Great Southern Railway (1919–21). Joining a local Sinn Féin club, he canvassed for the party in the College Green ward during the 1918 general election. Sent from an early age to Irish-language classes by his father (a Griffithite Sinn Féiner who gravitated to the Irish Volunteers, and helped mobilise supplies and transport prior to the Easter 1916 rising), he attended the Irish summer college in Spiddal, Co. Galway (1916–18), and joined the Gaelic League, becoming by early 1921 secretary of central branch. He wrote articles for the league's successive weekly organs, each in its turn suppressed by the authorities; despite regarding such writing as practice work within a language he was yet learning, he was selected best writer of Irish at the 1920 Dublin feis. Arrested with his father and two brothers just before Christmas 1920 when Black and Tans discovered a letter in Irish on his person during a house raid, he was imprisoned for several weeks in Wellington barracks. Leaving his railway job, he worked as a clerk in the clandestine office of the Dáil Éireann Department of Agriculture (1921–2). During the civil war, with departmental work at a standstill, he joined the Free State army as a commissioned officer assigned to general headquarters staff at Portobello barracks; having recently commenced legal studies at the King's Inns and UCD, he handled army legal matters, such as compensation claims for damage to property.
Called to the bar in 1924, after winning first place in the initial Free State junior administrative examinations (1925), he entered the civil service. Assigned to the Department of Education (1925–7), he was involved in launching the Irish-language publishing imprint An Gúm, intended to redress the paucity of reading material, apart from school texts, in the language. Transferred to the Department of Finance (1927), he served as estimates officer and parliamentary clerk, and was assistant secretary of the economy committee established by the Cumann na nGaedheal government to make recommendations on reductions in current expenditure. Appointed private secretary to the minister for finance (1931–2), he served both Ernest Blythe (qv) and the first Fianna Fáil minister, Sean MacEntee (qv). Promoted to assistant principal (1932), and to principal officer (1939), he represented the department on the Irish Folklore Commission, and served on the interdepartmental committee that, after the disastrous Kirkintilloch bothy fire (1937), investigated seasonal migration to Scotland. During the emergency he was regional commissioner for Galway and Mayo (1940–45), one of eight such officers charged with organising contingency preparations for dealing with the likely collapse of central administration in the event of invasion by any of the wartime belligerents.
Transferred out of Finance, he became assistant secretary (1945–8) and secretary (1948–67) of the Department of Posts and Telegraphs – the largest government department, administering both the postal service and telecommunications – in which offices he exerted a profound influence on the development of Irish broadcasting. He worked closely with Fianna Fáil minister P. J. Little (qv) to improve the range and quality of music offered by the broadcasting service, playing a large part in the decision to form and adequately staff a full Radio Éireann symphony orchestra. Representing Ireland in the several post-war conferences in Europe and America that reorganised the international regulation of broadcasting activities, he was among four vice-presidents of the Union Internationale de Radiodiffusion until its supplanting in western Europe in 1950 by the European Broadcasting Union; he was elected to the new body's administrative council (1953). Against long-prevalent government hostility, he continually promoted the concept of an independent public broadcasting corporation, in the meanwhile facilitating evolution of the broadcasting service as a semi-autonomous arm of his department. He established and served on a departmental committee that studied all facets of launching a television service (1953). In testimony before the television committee established in 1957 to consider applications from private interests to operate a proposed commercial television service, he argued vigorously for public ownership and operation, an intervention that strongly influenced the government volte-face of 1959 to reject a commercial service and establish an independent statutory public authority to control and operate both radio and the new television service.
A devout but liberal catholic, Ó Broin was prominent for many years in the Legion of Mary, founded by his close friend and civil-service colleague Frank Duff (qv). President of a legion presidium of writers, actors, and artists, he was first editor (1937–47) of the quarterly organ Maria Legionis. Sharing Duff's ecumenism, he belonged to the Mercier Society, the Pillar of Fire Society, and Common Ground, groups organised by Duff in the early 1940s to facilitate discussion between catholics and, respectively, protestants, Jews, and secular intellectuals; the first two were suspended amid disapproval by the catholic archbishop of Dublin, John Charles McQuaid (qv).
On retirement from the civil service (1967), Ó Broin concentrated on the parallel career of research and writing that he had cultivated over many years. Having begun writing articles and short stories in Irish from his earliest years in the Gaelic League, he published his first collection of short stories, Árus na ngábhad, in 1923. With the establishment of An Gúm (latter 1920s), he published three more collections of original short stories and translations of such masters of the genre as Pushkin, Mérimée, Maupassant, and Jerome K. Jerome. He translated several popular modern novels, including R. L. Stevenson's Kidnapped (An fuadach (1931)) and H. G. Wells's The war of the worlds (Cogadh na reann (1934)). Active as secretary, actor, and writer with the state-subsidised Gaelic Drama League (An Comhar Drámaíochta), which produced Irish-language plays, he published many plays in Irish, both original and translated. His best-selling book in Irish was Miss Crookshank agus coirp eile (1951), about the mummified corpses in the vaults of St Michan's church.
Ó Broin wrote prolifically on modern Irish history and biography. His Irish-language biography (1937) of Charles Stewart Parnell (qv), the first full-scale study of its kind in Irish since the commencement of the language revival, was a landmark publication, praised for the quality of its prose by such critics as Frank O'Connor (qv) and Sean O'Faolain (qv). Ó Broin's biography of Robert Emmet (qv), published in Irish (1954), and awarded the Douglas Hyde prize, pioneered the scholarly subversion of the romantic myth surrounding its subject, and included consideration of the political and social context; an enlarged and revised version, The unfortunate Mr Robert Emmet (1958), was Ó Broin's first substantial work in English. His subsequent biographies include: An Maidíneach: staraí na hÉireannach Aontaithe (1971), on the career of Richard Robert Madden (qv), first historian of the United Irishmen; Charles Gavan Duffy: patriot and statesman (1967); No man's man (1982), on civil servant Joseph Brennan (qv), first governor of the central bank; Michael Collins (1980); and Frank Duff (1982), a sympathetic but non-hagiographical treatment that was disliked by the Legion of Mary leadership. He edited In great haste: the letters of Michael Collins and Kitty Kiernan (1983).
Ó Broin took a largely biographical approach to historical writing, researching neglected aspects of pivotal historical events, and basing his studies on previously unexploited primary sources, often the papers of a single individual, whose career served as the linchpin of his narrative, filtering events through the perspective of that person. His chief contribution was in examining the relationship of British and Anglo-Irish figures to Irish nationalism during the revolutionary period, especially the perspectives of civil servants in the British administration. Dublin Castle and the 1916 rising (1966) described the experiences of Matthew Nathan (qv), the British under-secretary, and Arthur Hamilton Norway, the postal service secretary, based in the GPO; Ó Broin's own Irish-language translation was Na Sasanaigh agus Éiri amach na Cásca (1967). A companion study, The chief secretary: Augustine Birrell in Ireland (1969), emphasised the progressive policy of the British Liberal government, and the intractable difficulties posed thereto by Ulster intransigence and the rise of revolutionary nationalism. Protestant nationalists in revolutionary Ireland: the Stopford connection (1985) traced the evolving outlooks of two members of successive generations of a single family, Alice Stopford Green (qv) and Dorothy Stopford-Price (qv). W. E. Wylie and the Irish revolution (1989) concentrated on the prosecuting counsel at the courts martial of the leaders of the 1916 rising, and cast new light on the proceedings.
Another vein of Ó Broin's scholarship was his primary research into the history of Irish separatism, especially with sources in the Irish State Paper Office. Comhcheilg sa Chaisleán (1963), which he subsequently translated and expanded as The prime informer: a suppressed scandal (1971), dealt with William Henry Joyce (qv), an RIC district inspector embroiled in the conspiracy to fabricate damning charges against Parnell. Fenian fever: an Anglo–American dilemma (1971) treated the 1867 insurrection and its aftermath, while Revolutionary underground: the story of the Irish Republican Brotherhood 1858–1924 (1976) was a comprehensive survey. Ó Broin's autobiography was entitled Just like yesterday (1986).
Ó Broin received an honorary LLD from the NUI (1967). Elected a member of the RIA (1971), he was a council member (1974–6) and senior vice-president (1976–7), and chaired the group whose recommendations resulted in the academy's establishment of the National Committee on International Affairs. He was president of the Irish Historical Society (1973–4), and a member of the Irish Manuscripts Commission. He married (1925) Cait Ní Raghallaigh (d. 1984), an office assistant reared in Baltinglass, Co. Wicklow, whom he met in the Gaelic League; they had two sons and three daughters. After residing at addresses in the south city suburbs, they moved (mid 1930s) to Booterstown, Co. Dublin (living many years at 3 Vernon Terrace, last residence of R. R. Madden), and from there to the Stillorgan Road (1950s). He died 26 February 1990 in Dublin, and was buried in Deansgrange cemetery. His papers are in the NLI. His eldest son, Eimear Ó Broin, was an accomplished musicologist and assistant conductor of the several Radio Éireann orchestras (1953–89).