Esmonde, Sir Osmond Thomas Grattan (1896–1936), 12th baronet, diplomat and politician, was born 4 April 1896 at Ballynastragh, Co. Wexford, one of five children of Sir Thomas Henry Grattan Esmonde (qv) and his wife Alice Barbara, daughter of Patrick Donovan of Frogmore, Tralee, Co. Kerry. He was a cousin of Sir John Lymbrick Esmonde (qv), TD, and Sir Anthony Esmonde (qv), TD. Educated at Mount St Benedict School, Gorey, Co. Wexford, and Downside School, he attended Balliol College, Oxford (c.1915) and UCD (c.1917–19), though he did not graduate from either Oxford or the NUI.
Politicised by the 1916 rising, he joined Sinn Féin and campaigned in the 1918 general election for Roger Sweetman (1874–1954) in Wexford North, despite the fact that the IPP candidate was his own father. Thereafter he worked voluntarily for Sinn Féin, predominantly in attempting to secure international recognition for an independent Ireland, and personally defrayed any expense that he incurred in the course of that work. After a spell in London, where he assisted Arthur O'Brien (qv), he travelled to the USA with Éamon de Valera (qv) to secure recognition for an Irish republic and to help raise the first dáil loan. Late in 1920 Esmonde was despatched on a tour of the British dominions to seek recognition for the Irish republic. Sinn Féin emissaries were obviously controversial within the British empire, and on most occasions he was not welcome.
Travelling from New York to Vancouver, Esmonde departed (17 December 1920) for New Zealand and Australia on the Makura. After two days at Honolulu, where Governor McCarthy was (in Esmonde's later report) ‘a fairly good Irishman’, the Makura arrived at New Zealand (5 January 1921). However, the local authorities had been informed that there was a member of an Irish diplomatic mission on board, and Esmonde was prohibited from landing.
Shortly before the Makura arrived at Sydney (16 January) the Australian government published an additional regulation under the war precautions repeal act. The regulation – presumably passed to prevent Esmonde from disembarking – gave power to refuse entry to Australia to any British subject who refused to take an oath of allegiance. It had the desired effect, and he was forced to remain on board. The issue caused considerable controversy and attracted attention as far away as New York. To compound matters, a strike resulted in the Makura being towed into the middle of the harbour, and Esmonde was stranded there for more than six weeks.
The Makura finally left Sydney at the beginning of March and arrived in New Zealand, where Esmonde was again refused entry. Although officially restricted to the boat, which was in dry dock for a week, he reported that the largely Irish police force assisted him in visiting many of the Irish and catholic institutions of North Island. Later deported from Fiji, he arrived in Vancouver (29 March), where he was detained for two days before being granted permission to enter Canada. However, on 4 April Esmonde was arrested on charges of sedition. Following a disagreement at the end of the first trial, he was tried again and found guilty, although the judge refused to pass sentence. He eventually returned home during the summer of 1921.
After the signing of the truce in July 1921, Esmonde was sent to Paris to assist the diplomatic endeavours of Seán T. O'Kelly (qv); while there, he attended the Irish Race Congress. Early in 1922 the provisional government appointed him as its representative in Spain, and in 1923 he was recalled to Dublin, where he became assistant secretary at the Department of External Affairs. On 26 August 1923, the day before the general election, Esmonde departed Dublin as a member of the first Irish delegation to the League of Nations, at Geneva, Switzerland. Having being elected a Cumann na nGaedheal TD for Wexford, he returned to Dublin in mid September and resigned from the civil service.
In 1924 he joined the National Group under Joseph McGrath (qv) and, although rejoining Cumann na nGaedheal early in 1927, did not contest the June 1927 election. Reelected in September 1927, 1932, and 1933, he played an active role in the business of the dáil, where his speeches were not noted for their eloquence but for their wit and frankness. Chairman of the select dáil committee on local government (1928–30), he was also a member of the public accounts committee, where he was not averse to taking an independent line. After the boundary commission met in 1924–5, he argued that the executive council had no right to conduct negotiations with the British government on its own initiative, and that by signing the tripartite boundary agreement they had recognised the northern state on a coequal basis with the Irish Free State. On a less serious matter he annually called for the removal of the statute of Queen Victoria from the forecourt of Leinster House on aesthetic grounds. Dispirited by its continued presence, he placed a wreath of assorted vegetables under it in May 1933 with the inscription ‘Ave atque vale’.
A member of the national council of the Army Comrades Association (1936), he was a co-founder of the League of Youth and served on its central council. He told the dáil that he thought that Benito Mussolini was the ‘Abraham Lincoln of Africa’, who was ‘out to abolish the slave trade in spite of the sentimental sympathy of Great Britain’ (Dáil Debates, 6 November 1935). An avid observer of international affairs, he read many foreign daily newspapers, including the Spanish monarchist paper ABC, and was a member of the Irish Free State delegation to the Empire Parliamentary Association conference in Australia in 1926–7. Particularly interested in the politics of the Balkans, eastern Asia, and northern Africa, he wired his support to the leader of the Wafd party in Egypt in 1936.
Away from politics his abiding interests were soccer, archery, and aviation. President of both the Irish Free State Football Association and the Leinster Football Association, he was instrumental in sending the national team abroad to compete against other national sides. Owner of a private plane, in 1929 he was involved with a company that submitted plans to the government to establish a civil aviation service under Col. Russell and Col. James Fitzmaurice (qv), both former commandants of the Irish Free State air force. The proposals included provision of a government subsidy of £29,000, and a route between Dublin (Baldonnell) and London (Croydon). Vice-president of the Irish Aero Club, he flew his own small aeroplane, from which he distributed election literature in February 1932. He also painted and wrote verse, some of it under the pseudonym ‘Count Vladimir Ferdinand O'Mara’.
In June 1934 Esmonde was seriously injured in a car accident. Only weeks before his own death in 1936 he contested his father's 1928 will, in which Sir Thomas had left his entire estate to his second wife. Osmond argued in the high court that the deaths of his brother and mother, and the burning of Ballynastragh, had so affected Sir Thomas's mind that he had developed an insane dislike and suspicion of Osmond, his only surviving son. After a hearing of several days a settlement was announced in favour of his stepmother. Not surprisingly, Esmonde was commended on all sides for his chivalry in agreeing to this, for (despite a little pomposity) he was a likeable, self-deprecating, generous individual, with an impish sense of humour.
While receiving attention for heart trouble, he died 22 July 1936 at his flat, 30 Upper Pembroke St., Dublin, leaving estate valued at £4,873. He was unmarried and succeeded in the baronetcy by his uncle, Lt-col. Laurence Grattan Esmonde. There are two informal photographs in the possession of the National Portrait Gallery, London, in which he appears with Evan Frederic Morgan, 2nd Viscount Tredegar, and Viscountess Tredegar.