Dag Hjalmar Agne Carl Hammarskjøld was Secretary-General of the United Nations from 10 April 1953 until 18 September 1961 when he met his death in a plane accident while on a peace mission in the Congo.
Mr. Hammarskjøld was unanimously appointed Secretary-General of the United Nations by the General Assembly on 7 April 1953 on the recommendation of the Security Council. He was reelected unanimously for another term of five years in September 1957.
In 1955, following his visit to Peking, 30 December 1954 - 13 January 1955, 15 detained American fliers who had served under the United Nations Command in Korea were released by the Chinese People’s Republic. Mr. Hammarskjøld also traveled to many countries of Africa, Asia, Europe, the Americas and the Middle East, either on specific assignments or to further his acquaintance with officials of member governments and the problems of various areas.
On one of these trips, from 18 December 1959 to 31 January 1960, the Secretary-General visited 21 countries and territories in Africa – a trip he described later as “a strictly professional trip for study, for information”, in which he said he had gained a ‘kind of cross-section of every sort of politically responsible opinion in the Africa of today’.
Later in 1960, when President Joseph Kasa-Vubu and Prime Minister Patrice Lumumba of the Republic of the Congo sent a cable on 12 July asking ‘urgent dispatch’ of United Nations military assistance to the Congo, the Secretary-General addressed the Security Council at a night meeting on 13 July and asked the Council to act 'with utmost speed" on the request. Following Security Council actions the United Nations Force in the Congo was established and the Secretary-General himself made four trips to the Congo in connection with the United Nations operations there. The first two trips to the Congo were made in July and August 1960. Then, in January of that year, the Secretary-General stopped in the Congo while en route to the Union of South Africa on another mission in connection with the racial problems of that country. The fourth trip to the Congo began on 12 September and terminated with the fatal plane accident.
In other fields of work, Mr. Hammarskjøld was responsible for the organization in 1955 and 1958 of the first and second UN international conference on the peaceful uses of atomic energy in Geneva, and for planning a UN conference on the application of science and technology for the benefit of the less developed areas of the world held in 1962.
He held honorary degrees from Oxford University, England; in the United States from Harvard, Yale, Princeton, Columbia, Pennsylvania, Amherst, John Hopkins, the University of California, Uppsala College, and Ohio University; and in Canada from Carleton College and from McGill University.