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Who was Dag Hammarskjöld? -

Dag Hammarskjöld was a Swedish economist and diplomat who served as the second secretary-general of the United Nations, from April 1953 to September 1961.

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Top diplomat -

Hammarskjöld succeeded Trygve Lie, who on November 10, 1952, announced his resignation from the post. Lie was the UN's first chief.

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First day on the job -

On April 10, 1953, Hammarskjöld was elected to the office for a term of five years. In September 1957, he was reelected to another five-year term. He's pictured at his desk on the first day on the job.

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Negotiating with the Chinese -

In 1955 during his first tenure, Hammarskjöld visited China for talks with Prime Minister Zhou Enlai, ostensibly to negotiate the release of 15 US pilots captured by the Chinese during the Korean War.

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Resounding success -

China subsequently acquiesced, setting free the airmen. It was Hammarskjöld's first diplomatic success, with the UN chief feted by the press upon his return to New York.

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Mediating in the Middle East -

Throughout his term, the secretary-general frequently attempted to improve relations between Israel and the Arab states. He served as a mediator between David Ben-Gurion (pictured) and Gamal Abdel Nasser during the Suez Crisis of 1956.

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Establishing UNEF -

It was in 1956 that the United Nations Emergency Force (UNEF) was established by the United Nations General Assembly to secure a peaceful end to the crisis. Hammarskjöld is largely credited with developing UNEF as a peacekeeping force.

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"The greatest statesman of our century" -

Presidential candidate John F. Kennedy met Hammarskjöld, whom he greatly admired, in December 1960. Kennedy said of Hammarskjöld following his death, "I realize now that in comparison to him, I am a small man. He was the greatest statesman of our century."

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Crisis in Congo -

In June 1960, the Belgian Congo became the independent Republic of the Congo (now Democratic Republic of the Congo). Hammarskjöld invited the new prime minister, Patrice Lumumba (second left), and members of his cabinet to New York for talks.

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Quelling civil strife -

Meanwhile, the Congo had become a powder keg of civil strife and widespread violence. On August 15, 1960, a force of around 20,000 UN peacekeepers arrived in Élisabethville (now Lubumbashi) to restore order.

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Calling on Katanga -

That same month, Hammarskjöld visited Congo and met, among others, Moïse Tshombe, president of the secessionist State of Katanga. The breakaway province would soon play a central role in the fate that befell the secretary-general.

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Locking horns with Khrushchev -

Hammarskjöld's refusal to place peacekeepers in the service of Prime Minister Lumumba's constitutionally-elected government irked Soviet leader Nikita Khrushchev. The US stood by the secretary-general's decision: Patrice Lumumba was regarded by US officials as a dangerous, pro-communist radical.

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Lumumba executed -

Then in November, Patrice Lumumba was captured by forces loyal to Mobutu Sese Seko. Mobutu enjoyed support from Belgium and the United States, and eventually deposed Lumumba. He then ordered his execution, on January 17, 1961.

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Congo crisis deepens -

During Lumumba's detention, Hammarskjöld had made an appeal to the Congolese president, Joseph Kasa-Vubu, asking that his prime minister be treated according to due process. His request fell on deaf ears. The Soviets, meanwhile, demanded that the UN seek Lumumba's immediate release. The Kremlin also called for the immediate resignation of Hammarskjöld, the arrests of Mobutu and Moïse Tshombe, and the withdrawal of UN peacekeeping forces.

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Under pressure -

Hammarskjöld was in a corner. Answering Soviet criticism of his Congo operations, he said that if the UN forces were withdrawn from the Congo, "I fear everything will crumble."

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Soviet veto -

A pro-Lumumba resolution was defeated on December 14 by a vote of 8–2. Later, a Western resolution that would have given Hammarskjöld increased powers to deal with the Congo situation was vetoed by the Soviet Union.

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UN confronts Katanga -

United Nations units in the Congo were by now in direct conflict with Katangese troops under Moise Tshombe. Tshombe was fighting for an independent Katanga, and had announced that any intervention by UN troops would be met with force.

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Fateful decision -

It was into this turmoil that Dag Hammarskjöld flew on September 13, 1961, arriving at Léopoldville to head a peace mission.

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Hammarskjöld is killed -

On September 18, Hammarskjöld and 15 other passengers boarded a Douglas DC-6 airliner, his mission to negotiate a ceasefire between the warring parties. But the plane never reached its destination. Several hours into its flight, the DC-6 crashed near Ndola, Northern Rhodesia (present-day Zambia). All but one on board died in the crash. A 16th passenger passed away as a result of injuries a few days later.

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Suspicious circumstances -

The exact circumstances leading up to the tragedy have never been fully ascertained. The passenger who survived the initial impact, a man called Sergeant Harold Julien, spoke from his hospital bed of seeing "sparks in the sky" shortly before the crash. He also recalled an explosion. Julien died before he could divulge any more information.

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Blame game -

Three separate inquiries have been unable to come to a definitive conclusion about what happened on that fateful night. A 1962 Rhodesian inquiry concluded that pilot error was to blame; a later UN investigation could not determine the cause of the crash. Former US President Harry S. Truman was convinced Hammarskjöld had been assassinated. He "was on the point of getting something done when they killed him," he told reporters. "Notice that I said 'when they killed him.'"

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Foreign interference -

The KGB, the CIA, and MI6 were all active in Congo at the time of the crash, with all having vested interests in the outcome of the UN-Katanga conflict.

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Claims and conspiracies -

Several people who attended the crash scene claimed the DC-6 was riddled with bullets. A more lurid account suggested that Hammarskjöld had survived the crash but had been killed on the spot. These claims were dismissed as the wild imaginings of conspiracy theorists.

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UN mourns its chief -

Hammarskjöld's death shocked the international diplomatic community and the wider world. But without a full explanation as to what caused the crash, speculation and rumor began to circulate.

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Posthumous award -

Hammarskjöld's efforts to secure peace in the Congo and his wider work in trying to resolve various global crises led to him being the only posthumous recipient of the Nobel Peace Prize.

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Who killed Dag Hammarskjöld? -

Decades passed when, in 2014, newly declassified documents revealed that the American ambassador to the Congo sent a cable to Washington expressing his suspicion that the plane could have been shot down accidentally by a Belgian mercenary pilot known only as Beukels.

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Role of the NCA -

Intriguingly, it's believed that the US National Security Agency is in possession of radio intercepts that could help corroborate claims made by Beukels that he did indeed target the DC-6 by accident. The NCA radio intercepts have never been released publicly.

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Operation Celeste -

In 2016, the South African Truth and Reconciliation Commission published intelligence documents drawn up in 1998 suggesting that a bomb had been placed on board. The dossiers detailed an alleged plot, dubbed Operation Celeste, that was designed to kill Hammarskjöld. The CIA pointed the blame at Moscow while dismissing allegations that it was behind Hammarskjöld's demise as "absurd and without foundation."

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Plausible cause -

The following year a United Nations-mandated report found that it "appears plausible" that an external attack or threat may have led to the fatal plane crash that killed former UN Secretary-General Dag Hammarskjöld.

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In remembrance -

"There is a significant amount of evidence from eyewitnesses that they observed more than one aircraft in the air, that the other aircraft may have been a jet, that [the DC-6] was on fire before it crashed and/or that [it] was fired upon or otherwise actively engaged by another aircraft," noted the report. Pictured is the current UN Secretary-General, António Guterres, laying a wreath on the grave of Dag Hammarskjöld in Uppsala, Sweden. 

Sources: (Dag Hammarskjöld Foundation) (The Guardian) (Foreign Policy) (The Yale Review) (Britannica) (United Nations) 

See also: The United Nations' Sustainable Development Goals: Are they possible?

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