Seán Lester, Irish diplomat who is the last secretary-general of the League of Nations from August 31, 1940, to April 18, 1946, dies at Recess, County Galway, on June 13, 1959.

Lester is born on September 28, 1888, in Carrickfergus, County Antrim, as John Ernest Lester, the son of a Protestant grocer Robert Lester and his wife, the former Henrietta Ritchie. Although the town of Carrickfergus is strongly Unionist, he joins the Gaelic League as a youth and is won over to the cause of Irish nationalism. As a young man, he joins the Irish Republican Brotherhood (IRB). He works as a journalist for the North Down Herald and a number of other northern papers before he moves to Dublin, where he finds a job at the Freeman’s Journal. By 1919, he has risen to its news editor.

After the Irish War of Independence, a number of Lester’s friends join the new government of the Irish Free State. He is offered and accepts the position as director of publicity.

Lester marries Elizabeth Ruth Tyrrell in 1920 by whom he has three daughters.

In 1923, Lester joins Ireland’s Department of External Affairs. He is sent to Geneva in 1929 to replace Michael MacWhite as Ireland’s Permanent Delegate to the League of Nations. In 1930, he succeeds in organising Ireland’s election to the Council (or executive body) of the League of Nations for three years. He often represents Ireland at Council meetings and stands in for the Minister for External Affairs. He becomes increasingly involved in the work of the League, particularly in its attempts to bring a resolution to two wars in South America. His work brings him to the attention of the League Secretariat and begins his transformation from national to international civil servant.

When Peru and Colombia have a dispute over a town in the headwaters of the Amazon River, Lester presides over the committee that finds an equitable solution. He also presides over the less-successful committee when Bolivia and Paraguay go to war over the Gran Chaco.

In 1933, Lester is seconded to the League’s Secretariat and sent to Danzig (now Gdańsk, Poland), as the League of Nations’ High Commissioner from 1934 to 1937. The Free City of Danzig is the scene of an emerging international crisis between Nazi Germany and the international community over the issue of the Polish Corridor and the Free City’s relationship with the Third Reich. He repeatedly protests to the German government over its persecution and discrimination of Jews and warns the League of the looming disaster for Europe. He is boycotted by the representatives of the German Reich and the representatives of the Nazi Party in Danzig.

Lester returns to Geneva in 1937 to become Deputy Secretary General of the League of Nations. In 1940, he becomes Secretary General of the body, becoming the League’s leader a year after the beginning of World War II which shows that the League has failed its primary purpose. The League has only 100 employees, including guards and janitors, out of the original 700.

Lester remains in Geneva throughout the war and keeps the League’s technical and humanitarian programs in limited operation for the duration of the war. In 1946, he oversees the League’s closure and turns over the League’s assets and functions to the newly established United Nations.

Lester is given the Woodrow Wilson Award in 1945 and a doctorate of the National University of Ireland (NUI) in 1948.

Despite rumours that he would be prepared to stand for election as President of Ireland, Lester seeks no permanent office and retires to Recess, County Galway, in the west of Ireland, where he dies on June 13, 1959. In its obituary, The Times describes him as an “international conciliator and courageous friend of refugees.”

In August 2010, a room in the Gdańsk City Hall, the building that had been Lester’s residence during his stay, is renamed by Mayor Paweł Adamowicz as the Seán Lester Room.

Lester’s granddaughter, Susan Denham, is Chief Justice of Ireland for the Supreme Court of Ireland from 2011 to 2017.