The death of Dag Hammarskjöld, secretary general of the United Nations, was a turning point in modern history. When his DC-6 plunged to earth on Sept. 18, 1961, he was trying to resolve a crisis that was tearing apart a vast and newly independent nation, Congo. The solution he was seeking would have undermined Western power in Africa. It would also have pulled much of Congo’s immense mineral wealth away from a Belgian mining conglomerate, Union Miniere du Haut Katanga, that was one of the world’s most powerful corporations.

Moments after midnight in the heart of Africa, a plane carrying one of the 20th century’s greatest peacemakers fell from the air. The crash site was immediately sealed. A quick inquiry blamed pilot error. The wreckage was buried. Only now, more than half a century later, is a fuller truth beginning to emerge.

A plane carrying UN Secretary General Dag Hammarskjold, one of the 20th century’s greatest peacemakers, fell from the air in the heart of Africa. More than a half century later, the truth beginning to emerge.


An exhaustive study of the case published in 2011, “Who Killed Hammarskjöld? The UN, the Cold War and White Power in Africa,” found that “whatever the details, his death was almost certainly the result of a sinister intervention.” A new documentary film — the product of a six-year investigation — goes further. It concludes that Hammarskjöld’s plane was shot down, names the now-deceased Belgian pilot who allegedly committed the crime, and offers the first detailed look inside a secret para-military arm of South Africa’s apartheid regime that may have designed the plot.

World attention was riveted by the violent crisis that shook Congo in the weeks and months after it became independent from Belgium in 1960. The country’s first elected prime minister, Patrice Lumumba, was a fiery nationalist who wanted to assert government control over Congo’s subsoil riches. It was an audacious challenge to Western political and economic interests, comparable to Iran’s nationalization of its oil industry and Guatemala’s decision to force the United Fruit Company to sell its unused properties so they could be divided among peasant families. The CIA had crushed those challenges by organizing a coup in which the Iranian government was overthrown in 1953, and then doing the same in Guatemala a year later. In 1960, President Dwight Eisenhower ordered the CIA to assassinate Lumumba. The agency’s chief chemist, Sidney Gottlieb, flew to the Congo and delivered a batch of poison to the local CIA station chief. According to the station chief’s memoir, he asked who ordered the assassination and Gottlieb replied: “President Eisenhower.” Before the poison could be used, Congolese squads under Belgian command captured and executed Lumumba.


That might have ended the threat to the mining conglomerate, which had arranged to have the province where it operated, Katanga, declared an independent nation. But it did not, because Hammarskjöld refused to accept the breakup of Congo and insisted that foreign corporations working there must submit to Congolese authority. This was part of his wider effort to end colonialism in Africa, which included ending white rule in South Africa. He knew he was making enemies.

“We have countered efforts from all sides to make the Congo a happy hunting ground for national interests,” he said shortly before his death. “To be a roadblock to such effort is to make yourself the target of attack from all those who see their plans thwarted.”

Not satisfied with making statements like that in New York, Hammarskjöld traveled to Congo so he could directly confront secessionists and demand that they accept the country’s independence and unity. He was on that mission when he and 15 others aboard his plane perished. The world was deeply shaken. President John F. Kennedy called Hammarskjöld “the greatest statesman of our century” and added: “In comparison to him, I am a small man.” Former president Harry Truman was among those who sensed conspiracy. “Dag Hammarskjöld was on the point of getting something done when they killed him,” Truman said. “Notice that I said ‘When they killed him.’ ”


The new documentary film, called “Cold Case Hammarskjöld,” takes the story further. Among those who testify on camera is a former National Security Agency officer who was serving at a radio surveillance base in Cyprus on the night of the crash and monitored a pilot saying, “I hit it! There are flames coming out of it!” He said the NSA has refused his request to obtain transcripts of that night’s tapes because they are “top secret on national security grounds.”

Most dramatic is the testimony of a veteran of the clandestine para-military force implicated in the crime who says he decided to break his oath of secrecy because he feels guilt and needs “personal closure.” He then provides dramatic details of what he describes as an assassination plot involving the Belgian, South African, British, and American intelligence services. “Africa would have been a completely different continent today if Dag Hammarskjöld was allowed to live and follow through on his mandate,” he muses. A note at the end of the film says that this witness has left South Africa, lives in hiding, and is providing information to UN investigators.


After his death, Hammarskjöld became the only person ever to be awarded the Nobel Peace Prize posthumously. His death is the greatest tragedy in the history of the United Nations and one of the enduring mysteries of the Cold War. It is now closer than ever to being solved.

“Cold Case Hammarskjöld” is now playing at CinemaSalem.

Stephen Kinzer is a senior fellow at the Watson Institute for International and Public Affairs at Brown University.