Dag Hammarskjöld was born in Jönköping to the noble family Hammarskjöld (also spelled Hammarskiöld or Hammarsköld). He spent most of his childhood in Uppsala. His home there, which he considered his childhood home, was Uppsala Castle. He was the fourth and youngest son of Hjalmar Hammarskjöld, Prime Minister of Sweden from 1914 to 1917.
Hammarskjöld studied first at Katedralskolan and then at Uppsala University. By 1930, he had obtained Licentiate of Philosophy and Master of Laws degrees. Before he finished his law degree he had already obtained a job as Assistant Secretary of the Unemployment Committee.
From 1930 to 1934, Hammarskjöld was Secretary of a governmental committee on unemployment. During this time he wrote his economics thesis and received a doctorate from Stockholm University. In 1936, he became a secretary in Sweden’s central bank, the Riksbank. From 1941 to 1948, he served as chairman of the Riksbank’s General Council.
Hammarskjöld quickly developed a successful career as a Swedish public servant. He was state secretary in the Ministry of Finance 1936–1945, Swedish delegate to the Organization for European Economic Cooperation 1947–1953, cabinet secretary for the Ministry of Foreign Affairs 1949–1951 and minister without portfolio in Tage Erlander’s government 1951–1953.
He helped coordinate government plans to alleviate the economic problems of the post-World War II period and was a delegate to the Paris conference that established the Marshall Plan. In 1950, he became head of the Swedish delegation to UNISCAN, a forum to promote economic cooperation between the United Kingdom and the Scandinavian countries. Although Hammarskjöld served in a cabinet dominated by the Social Democrats, he never officially joined any political party.
In 1951, Hammarskjöld was vice chairman of the Swedish delegation to the United Nations General Assembly in Paris. He became the chairman of the Swedish delegation to the General Assembly in New York in 1952. On 20 December 1954, he was elected to take his father’s vacated seat in the Swedish Academy.
31 March 1953, the Security Council voted 10-0-1 to recommend Hammarskjöld to the General Assembly, with an abstention from Nationalist China. Shortly after midnight on 1 April 1953, Hammarskjöld was awakened by a telephone call from a journalist with the news, which he dismissed as an April Fool’s Day joke. He finally believed the news after the third phone call. The Swedish mission in New York confirmed the nomination at 03:00 and a communique from the Security Council was soon thereafter delivered to him. After consulting with the Swedish cabinet and his father, Hammarskjöld decided to accept the nomination. He sent a wire to the Security Council:
With strong feeling personal insufficiency I hesitate to accept candidature but I do not feel I could refuse to assume the task imposed on me should the [UN General] Assembly follow the recommendation of the Security Council by which I feel deeply honoured.
Later in the day Hammarskjöld held a press conference at the Swedish Foreign Ministry. According to diplomat Sverker Åström, he displayed an intense interest and knowledge in the affairs of the UN, which he had never shown any indication of before.
The U.N. General Assembly voted 57-1-1 on 7 April 1953 to appoint Dag Hammarskjöld as Secretary-General of the United Nations. Hammarskjöld was sworn in as Secretary-General on 10 April 1953. He was unanimously reelected on 26 September 1957 for another term, taking effect on 10 April 1958.
Hammarskjöld (age 48) outside the UN headquarters in New York City, 1953
Immediately following the assumption of the Secretariat, Hammarskjöld attempted to establish a good rapport with his staff. He made a point of visiting every UN department to shake hands with as many workers as possible, eating in the cafeteria as often as possible, and relinquishing the Secretary-General’s private elevator for general use. He began his term by establishing his own secretariat of 4,000 administrators and setting up regulations that defined their responsibilities. He was also actively engaged in smaller projects relating to the UN working environment; for example, he spearheaded the building of a meditation room at the UN headquarters, where people can withdraw into themselves in silence, regardless of their faith, creed, or religion.
During his term, Hammarskjöld tried to improve relations between Israel and the Arab states. Other highlights include a 1955 visit to China to negotiate the release of 11 captured US pilots who had served in the Korean War, the 1956 establishment of the United Nations Emergency Force, and his intervention in the 1956 Suez Crisis. He is given credit by some historians for allowing participation of the Holy See within the United Nations that year.
In 1960, the newly independent Congo asked for UN aid in defusing the Congo Crisis. Hammarskjöld made four trips to Congo, but his efforts toward the decolonisation of Africa were considered insufficient by the Soviet Union; in September 1960, the Soviet government denounced his decision to send a UN emergency force to keep the peace. They demanded his resignation and the replacement of the office of Secretary-General by a three-man directorate with a built-in veto, the “troika”. The objective was, citing the memoirs of Soviet leader Nikita Khrushchev, to “equally represent interests of three groups of countries: capitalist, socialist and recently independent”.
On 10 November 1952 Trygve Lie announced his resignation as Secretary-General of the United Nations. Several months of negotiations ensued between the Western powers and the Soviet Union, without reaching an agreement on his successor. On 13 and 19 March 1953, the Security Council voted on four candidates. Lester B. Pearson of Canada was the only candidate to receive the required majority, but he was vetoed by the Soviet Union. At a consultation of the permanent members on 30 March 1953, French ambassador Henri Hoppenot suggested four candidates, including Hammarskjöld, whom he had met at the Organisation for European Economic Cooperation.
The superpowers hoped to seat a Secretary-General who would focus on administrative issues and refrain from participating in political discussion. Hammarskjöld’s reputation at the time was, in the words of biographer Emery Kelèn, “that of a brilliant economist, an unobtrusive technician, and an aristo-bureaucrat”. As a result, there was little to no controversy in his selection; the Soviet permanent representative, Valerian Zorin, found Hammarskjöld “harmless.”Zorin declared that he would be voting for Hammarskjöld, surprising the Western powers. The announcement set off a flurry of diplomatic activity. British Foreign Secretary Anthony Eden was strongly in favor of Hammarskjöld and asked the United States to “take any appropriate action to induce the [Nationalist] Chinese to abstain.” (Sweden recognized the People’s Republic of China and faced a potential veto from the Republic of China.) At the U.S. State Department, the nomination “came as a complete surprise to everyone here and we started scrambling around to find out who Mr. Hammarskjold was and what his qualifications were”.The State Department authorized Henry Cabot Lodge Jr., the US Ambassador, to vote in favor after he told them that Hammarskjöld “may be as good as we can get”.
On 18 September 1961, Hammarskjöld was en route to negotiate a cease-fire between United Nations Operation in the Congo forces and Katangese troops under Moise Tshombe. His Douglas DC-6 airliner SE-BDY crashed near Ndola, Northern Rhodesia (now Zambia). Hammarskjöld perished as a result of the crash, as did all of the 15 other passengers.Hammarskjöld’s death set off a succession crisis at the United Nations, as there was no line of succession and the Security Council had to vote on a successor.
The circumstances of the crash are still unclear. A 1962 Rhodesian inquiry concluded that pilot error was to blame, while a later UN investigation could not determine the cause of the crash. There is evidence suggesting the plane was shot down.A CIA report claimed the KGB was responsible.
The day after the crash, former U.S. President Harry Truman commented that Hammarskjöld “was on the point of getting something done when they killed him. Notice that I said ‘when they killed him’.”
A Swedish aid worker whose father worked for the UN in Zambia, wrote in 2011 that he believed Hammarskjöld’s death was a murder committed, in part, to benefit mining companies like Union Minière, after Hammarskjöld had made the UN intervene in the Katanga crisis. Björkdahl based his assertion on interviews with witnesses of the plane crash near the border of the DRC with Zambia and on archival documents.
In 2013 accident investigator Sven Hammarberg was asked by the International Commission of Jurists to investigate Hammarskjöld’s death.
On 16 March 2015, United Nations Secretary-General Ban Ki-moon appointed members to an Independent Panel of Experts to examine new information related to Hammarskjöld’s death. The three-member panel was led by Mohamed Chande Othman, the Chief Justice of Tanzania, and included Kerryn Macaulay (Australia’s representative to the ICAO) and Henrik Larsen (a ballistics expert from the Danish National Police). The panel’s 99-page report, released 6 July 2015, assigned “moderate” value to nine new eyewitness accounts and transcripts of radio transmissions. Those accounts suggested that Hammarskjöld’s plane was already on fire as it landed and that other jet aircraft and intelligence agents were nearby.
In 2016, the original documents from the 1998 South African investigation surfaced. Those familiar with the investigation cautioned that even if authentic, the documents could have been initially authored as part of a disinformation campaign.
In 2019, the documentary film Cold Case Hammarskjöld by Danish filmmaker Mads Brügger claimed that Jan van Risseghem had told a friend that he shot down Hammarskjöld’s aircraft. This went against the official stance maintained by van Risseghem’s family that he was not involved in the death of Hammarskjöld. According to an interview with van Risseghem’s wife, he was in Rhodesia negotiating the purchase of a plane for the Katanga Air Force and the logbooks provided “proof that he was not flying for Katanga at the time”. The documentary crew interviewed multiple colleagues of van Risseghem for the film, all of whom supported their theory. In an interview with Swedish historian Leif Hellström, van Risseghem claimed that he was not in southern Africa at the time it happened, and dismissed the idea of being potentially involved as “fairy stories”.
In Hammarskjöld’s 1959 will he left his personal archive to the National Library of Sweden.