Cremins, Francis (‘Frank’) Thomas (1885–1975), diplomat, was born 20 January 1885 in the workhouse at Carrick-on-Suir, Co. Tipperary, son of Patrick Cremins, teacher, and Honoria Cremins (née Mulcahy; 1845–1931), matron of the Carrick-on-Suir workhouse. Cremins entered the GPO as an unpaid learner in 1900 and worked his way up through the ranks to become a lower clerical officer by 1922. He transferred to the Department of External Affairs in July 1922, serving in its publicity section (1922–5). When that section was closed down he moved to the Department of Lands and Agriculture as a higher executive officer, where he remained until May 1929. He returned to external affairs in 1929 as head of the League of Nations section of the department (1929–34). Cremins played an important role in managing the campaign for the Irish Free State's election to the council of the League in 1930. These were years when the state was in the heyday of its membership of the League of Nations and had a temporary seat on the League council (1930–33).
In May 1934 he was appointed permanent delegate to the League of Nations, replacing Seán Lester (qv). Through the 1930s his reports on Europe's descent into war provided Dublin with an overview of the decline of the League of Nations (an institution about which Cremins, an advocate of realpolitik, suffered no romantic illusions) and the rise of fascist and totalitarian states bent on war and territorial expansion. His reports to Dublin during the final days of peace in 1939 provided a vivid day-to-day account of the rumours and dashed hopes in Europe on the brink of catastrophe. After the German invasion of Poland, Cremins's reports graphically portrayed the uncertainty of the period and showed Switzerland's preparations to defend her borders, should (as Cremins suggested was the prevalent feeling) German forces cross the Swiss border. On 2 September, the day after the invasion of Poland, he reported to Dublin that ‘a European war had practically begun . . . a fight to the finish . . . being the only possible solution’. Cremins remained in Geneva until 1940, though the League was reduced to a skeleton operation through the war under its last secretary general, Seán Lester. Dublin continued to pay its yearly contribution to the League through the war. When Ireland established a legation in Berne in May 1940, Cremins was appointed chargé d'affaires in Switzerland.
Through the second world war Cremins's post in neutral Switzerland was a key link in the thinly stretched Irish diplomatic chain across Europe. He channelled information to the Irish chargé in Berlin, remained in close contact with the Irish chargé in Lisbon, and kept in contact with his former colleague and close friend, Seán Lester, at the League of Nations in Geneva. Cremins's health was poor, and after the war he was the only senior Irish diplomat serving overseas who did not return for Éamon de Valera's (qv) heads-of-missions conference on the future direction of Irish foreign policy, which was held in Dublin in September 1946. He remained in Berne to July 1949, when he retired from the public service.
Cremins died 1 August 1975 at his home in Dalkey, Co. Dublin, and was buried in Deansgrange cemetery. He was unmarried and left an estate of £16,585.