Lester, Seán (John Ernest) (1888–1959), diplomat, was born 27 September 1888 at Woodburn, Carrickfergus, Co. Antrim, son of Robert John Lester, owner of a Belfast grocery shop, and Henrietta Mary Lester (née Ritchie). Briefly educated at the Methodist College, Belfast (1901–2), he left school aged thirteen or fourteen, and his many jobs included working for the Belfast & County Down Railway in Bangor. According to his daughter, Dorothy, he was colour-blind, ‘which would never do for a station master’. In 1905, aged seventeen, he began a career in journalism with the unionist North Down Herald, where one of his colleagues was Ernest Blythe (qv). In Belfast he discovered the Gaelic League; and as he was, like Blythe, a protestant, nationalism came to him as a revelation. In 1908 he joined the Irish Republican Brotherhood (IRB), being sworn in by Bulmer Hobson (qv) at Portadown railway station. In 1909 he joined Sinn Féin. He was chief reporter of the Dublin Evening Mail and the Dublin Daily Express, both unionist papers, and also worked for the Galway Connaught Tribune. Due to the confusion over the countermanding order by Eoin MacNeill (qv), and as an associate of MacNeill and Hobson, who opposed the rising, Lester did not come out in 1916. After the rising he joined the Freeman's Journal where he was news editor, a post he held to 1922.
In 1923, through his friendship with Blythe, Lester joined the fledgling Irish Free State Department of External Affairs as an officer in the publicity department. He became director of publicity (1925–9). In April 1929 he moved to Geneva as Irish Free State permanent representative to the League of Nations. He held this post until January 1934. As Irish permanent representative he was responsible for the formulation of Irish League policy, and along with the Irish representative to France, Gerard O'Kelly (qv), he played an essential part in the Free State's successful election to the League council (September 1930). At Geneva Lester represented Ireland at numerous international conferences, as well as serving as Irish representative on the council of the League from 1930 to 1933 on the occasions when the minister for external affairs was not present. Lester was also a member of the League of Nations preparatory commission for the disarmament conference, and represented Ireland at sessions of the disarmament conference from 1932 to 1933. He held the post of president of the conciliation committee for the Peru–Colombia (Leticia) and Bolivia–Paraguay (Gran Chaco) disputes. According to an obituary in The Times, ‘the rights of small nations and minorities brought out his particular abilities’.
Lester's belief in the League and in the role of the small states as League supporters brought him to the attention of the League secretariat. In autumn 1933 he was seconded to the secretariat, the first Irish diplomat to serve in an international institution. He took up office as League high commissioner for Danzig (Gdansk) in January 1934. His activities were primarily diplomatic, but he had to mediate between rival German and Polish groupings in the city. He commented to Éamon de Valera (qv) in 1934 that Poles, Germans, and Danzigers were all convinced that an Irishman would understand and defend their own positions. His role was to broker a compromise between the competing factions.
On return to Geneva in February 1937 Lester was promoted to the post of deputy secretary general of the League. He played a mainly administrative role until the outbreak of the second world war (1939) left him responsible for gathering the pieces of the discredited League together. As a firm believer in the League, he was brought into conflict with the pro-Nazi secretary general, Joseph Avenol, who expected a German victory and wanted to make the League pro-Axis. Lester opposed this move and was supported by Adolfo Costa du Rels, president of the League council. Lester became acting secretary general (replacing Avenol, who had resigned) on 4 September 1940 and held the post until 1946. He spent the war in Geneva, carrying on the non-political work of the League with a skeleton staff. He was determined to keep the League's organisation together for the postwar era, and later wrote: ‘In normal times I would not have accepted the post of secretary general, but I could not refuse it with the world falling about our ears.’ Lester regarded these years as the hardest of his life. Not only was the League far from secure as an institution, but until 1943 a German invasion of Switzerland was considered likely.
In 1945 Lester represented the League at the San Francisco conference that founded the United Nations, but he was assigned no role in the new organisation. The UN was to symbolise a new beginning; former League officials could not be allowed to taint it. With America and the Union of Soviet Socialist Republics (USSR) dominating the postwar order, a representative of an organisation of which they had few fond memories stood in low esteem. Lester was also looked on with disdain as a citizen of a neutral state. In 1946 he prepared for the twenty-first and final assembly of the League, which opened on 8 April and awarded him the title of full secretary general, retrospective from 1940. It was his final task formally to dissolve the League and dispose of its assets. On 31 July 1947 the League officially ceased to exist.
Lester retired to Recess, Co. Galway, to fish and garden. Despite offers, he did not serve the Irish government in any further posts. As an international civil servant, he felt he could not return to serve any one country. There was some speculation that he would be a potential candidate for the presidency of Ireland in 1945, but this was not to be. He was awarded an honorary Doctor of Laws (LLD) degree from Dublin University (1947) and an equivalent honour from the National University of Ireland (NUI) in 1948. In 1945 the Woodrow Wilson Foundation made an award to him for his distinguished service in maintaining the League throughout the war. Also in 1945 he took over the post of president of the permanent Norwegian–Swiss conciliation commission. In 1956 Lester was appointed for six years to the Irish national group that nominated candidates to fill vacancies in the membership of the International Court of Justice. He died 13 June 1959 and is buried with his wife in Clifden, Co. Galway.
He married (1920) Elizabeth Ruth, daughter of Alderman J. Tyrell of Belfast and sister of Air Vice-marshal Sir William Tyrrell (qv). They had three daughters: Ann, Dorothy and Patricia.
More information on this entry is available at the National Database of Irish-language biographies (Ainm.ie).