Hammarskjöld, Dag (Hjalmar Agne Carl)

Swedish secretary general of the United Nations (UN) 1953–61. His role as a mediator and negotiator, particularly in areas of political conflict, helped to increase the prestige and influence of the UN significantly, and his name is synonymous with the peacekeeping work of the UN today. He was killed in a plane crash while involved in a controversial peacekeeping mission in Congo (now the Democratic Republic of Congo). He was posthumously awarded the Nobel Prize for Peace in 1961 for his peacekeeping work as secretary general of the UN.

Hammarskjöld was born in Jönköping, Sweden, the son of the Swedish prime minister 1914–17, and attended university in Uppsala and Stockholm, where he read economics. After serving as chairman of the bank of Sweden, he entered government, and in 1951 joined the Swedish delegation to the UN. In 1953 he was elected to replace the first secretary general of the UN, Trygve Lie, and was reelected in 1957.