The world's most prestigious prize was created just 100 years ago this year by Alfred Nobel, a Swedish chemist best known as the inventor of dynamite. Announcing the committee's decision is Oslo, Gunnar Berger, the chairman, said, "The Norwegian Nobel Committee wishes in its centenary year to proclaim that the only negotiable route to global peace and cooperation goes by way of the United Nations."

Committee members, who actually made their choice on Sept. 28, just 17 days after the terrorist attacks on New York's World Trade Center and the Pentagon, outside Washington, hailed the UN and its administrative head for their work for "a better organized and more peaceful world" -- including its leadership of global campaigns against international terrorism, the HIV/AIDS pandemic and poverty and ignorance.

Annan, a 63-year-old, US-educated native of the West African nation Ghana, was singled out for breathing new life into the UN, which was weak and floundering -- and widely discredited in Western capitals -- when he took charge in 1997, replacing Boutros Boutros-Ghali of Egypt. Boutros-Ghali had lost America's confidence and was denied a second term that otherwise would have been normal. Annan will claim his own new five-year mandate on January 1.

In a resounding tribute to the incumbent's success in turning the UN around, the Security Council and General Assembly acted with extraordinary dispatch this past summer to reappoint him by acclamation. He is the seventh person to hold the office. The first was Norway's own Trygve Lie, whose tenure was cut short by Moscow's disfavor following a controversial role in the Korean War, the UN's most famous "police action" against communist aggression, and during the McCarthy era in the US.

Characteristically, the quiet-spoken, mild-mannered Annan looked beyond his personal satisfaction over receiving the Peace Prize after his spokesman Fred Eckhard awakened him Friday to pass on the good news from Oslo. "It's a wonderful feeling," he responded, "and a great encouragement for us and the Organization, for the work we have done until now. It's a great recognition for the staff."

Prior to his elevation, he was a staff member himself, having joined the UN system some 40 years ago at the World Health Organization after briefly testing life in the private sector on graduation from Macalester College, a liberal arts institution in St. Paul, Minnesota, known for its somewhat leftish outlook. Annan, who attended a boarding school in Ghana before coming to the US, also studied at the Massachusetts Institute of Technology.

An aristocrat by birth and son of a prominent tribal chieftain, he was among Ghanaians who worked and spoke out for his country's independence from British colonialism, while vigorously opposing change through violences and the trend toward autocracy that was common in Africa at the time -- and persists to this day. He recently recalled that his frequent exhortations in behalf of democracy and free elections prompted his classmates to nickname him "Demo."

Naming the United Nations itself to share the $946,000 Prize, rather than declaring Annan the peace laureate outright, appears to be the Nobel Committee's acknowledgement of the UN's 56-year struggle unde a series of leaders to preserve world peace, defend democratic systems and enhance the lives of billions of people, especially the citizens of poor states plagued by physical and economic ills, including grave abuses of human rights, and now the scourge of AIDS that Annan has made a personal cause.

UN agencies have been honored previously by the Peace Prize Committee -- the only Nobel selection group to be located in Norway; the others are based in Sweden -- and a former UN Secretary General also was awarded the Prize, albeit posthumously. That was Dag Hammarskjold, who was killed 40 years ago this year in a plane crash in Africa where he was on a Congo peace mission. Hammarskjold was Swedish.

Another UN winner was Ralph J. Bunche, an American UN official who received the award for his work as a Middle East peace negotiator. UN peacekeeping forces were honored with the 1988 Prize and the UN High Commissioner for Refugees won twice, in 1954 and 1981. Unicef, the United Nations Children's Fund, received the Prize in 1965.

The Norwegian committee has a reputation for an element of quirkiness in its decisions and in some quarters is considered overly liberal. This does not, however, reduce the respect its members enjoy. Except perhaps for a few political critics on the right, this year's awards are expected to be widely approved, not least by President George W. Bush, who has already begun to look to the UN for help in nation-building in Afghanistan when the guns are silenced.

Committee chairman Berger said the events of Sept. 11 and their aftermath "further underpinned" this year's choices. In his comments, Annan said the Prize "reinforces us in pursuing the search for peace."

The award is bound to have given his wife, Nane, special satisfaction. She is Swedish, a niece of Raul Wallenberg, a Swedish businessman and diplomat credited with saving the lives of thousands of Jews in World War II. He disappeared mysteriously and now is believed to have died in a Soviet concentration camp. Nina Lagergren, his sister, was reported from Oslo to have hailed the Prize for Annan with the comment that he "is an immensely fine person -- very warm and wise, an unpretentious person with great humor and integrity, a role model for mankind."

Among the factors that the committee may have taken into account was his own long-time leadership of the UN department of peacekeeping operations as an under secretary general before he was tapped for the top job. His term there was not without blemish but the department was constantly up against tremendous odds, including differences of opinion among the major powers on whether and how to involve the UN in efforts to contain conflicts.

In acknowledging that the UN staff now shares the Nobel honor, Annan will have had in mind more than 200 UN employees who lost their lives in the field, including the first casualties in the current war in Afghanistan -- four members of a team sent there to find and neutralize landmines, of which there are estimated to be several million, after two decades of external and fratricidal conflict.

The UN and Annan were up against formidable competition for the Prize. The 136 nominees included the International Committee of the Red Cross, the UN's own international war crimes tribunals, the international governing body for the world's most popular sport soccer, the ailing Pope John Paul II and the European Court of Human Rights.

The award is to be presented to Annan, who presumably will accept it in his own right as well as on the UN's behalf, by the king of Sweden at a white tie affair in Stockholm on December 10, Nobel's birthday. Coincidentally, this is also Human Rights Day, the anniversary of the UN Declaration of Human Rights that is Eleanor Roosevelt's lasting legacy and which this Secretary General has worked mightily to implement and defend.