The Norwegian Foreign Minister became the UN's first Secretary General after the rejection of names including Winston Churchill and Dwight Eisenhower. The Great Powers expected a tame bureaucrat; instead Lie quickly defined an activist role by intervening in the Security Council in an early dispute between Moscow and the West over Iran.
No fewer than 50 Soviet vetoes were cast in the Security Council during his tenure. He was boycotted by Moscow in his second term; resigned in frustration in 1953. A former wrestler, Lie was not considered to have soaring intellect or deep vision.
DAG HAMMARSKJOLD, Swedish, 1953-1961
Hammarskjold, from aristocratic Swedish stock, is now revered as the wisest and most skilled leader the UN has ever had. He fought back the tentacles of the McCarthy-era witch-hunts and travelling to Peking to demand the release of US airmen shot down by China. In his interventions in the Suez crisis, Hammarskjold laid down the notion of the Secretary General as neutral mediator in armed conflict and dispatched the first UN peacekeeping force.
The legend of Hammarskjold was set in stone after his death in a plane crash over Africa - ruled an accident - while he was attempting to negotiate peace for the Congo.
U THANT, Burmese. 1961-1971
The ambassador to the UN from Burma, U Thant oversaw a decade marked by the Cuban missile crisis, the Vietnam War, the invasion of Czechoslovakia and the Six Day War in the Middle East. In spite of his passive nature, U Thant also believed in the Secretary General's duty to intervene in such events. His abortive mediation efforts in South Vietnam earned him contempt from Washington while his actions during the Cuban Missile crisis also infuriated Moscow.
History remembers U Thant as weak and essentially invisible. The image was partly born of his public passivity and calmness that came with his devout belief in Buddhism.
KURT WALDHEIM, Austrian. 1972-1981
Waldheim took over in an era when the UN's standing in the world was at rock-bottom. Waldheim was seen as weak and an appeaser of the main powers. "I have not got the real power to force anyone to do anything," he lamented.
Waldheim will for ever be associated with the revelations of his Nazi past. It has since been surmised that Russia, for one, knew of his war crime activities and used it to its advantage. What is most remarkable is that the original documents that incriminated him and that charged him with "murder" and "putting hostages to death" had all along been held in UN archives. No-one had bothered to check them.
JAVIER PEREZ de CUELLAR, Peruvian. 1982-1991
A long-time UN bureaucrat, Perez de Cuellar is credited with taking advantage of the Cold War's close to give the UN fresh standing. He began his tenure by complaining that the Security Council was passing resolutions that "were increasingly ignored or defied"; by the time of his retirement he was hailing an organisation in the midst of "renaissance".
He saw the UN mediate to end the Iran-Iraq war and the conclusion of the Lebanon hostage crisis. An early nightmare for Perez de Cuellar came with the 1982 Falklands crisis. He attempted to mediate a settlement, even suggesting that the islands live under three flags.
BOUTROS BOUTROS-GHALI, Egyptian. 1992-1996
Elected with French backing almost by accident in 1991 - the British did not want him and the Americans supported him in the belief he could not win - Boutros-Ghali brought the UN a flavour of patrician diplomacy. In spite of his age, 70 when he arrived, he proved a forceful and fiercely independent Secretary General. That independence quickly began to grate with the Clinton administration, which erroneously came to assign to Boutros-Ghali much of the blame for the debacle in Somalia. Boutros-Ghali, who was even ridiculed in America because of his name, was later to be similarly maligned over the prolonged failure of the peace mission in Bosnia.