He joined his nation’s international ministry in 1965 and, eight years later, was posted as ambassador to Tanzania. He was additionally his nation’s envoy to Mozambique, Somalia and Zambia at a time when the continent’s tide of independence was transferring southward. Zambia had achieved its independence from Britain underneath Kenneth Kaunda in 1964; Mozambique, together with different former Portuguese colonies in Africa, did so in 1975. In 1968, Mr. Ahtisaari married Eeva Hyvarinen, a secondary-school trainer, with whom he had a son, Marko. They survive him.
The United Nations appointed Mr. Ahtissari commissioner and particular consultant to Namibia in 1977, starting the lengthy and tangled path that led to the nation’s independence 13 years later. In 1991, he took over as head of Finland’s Foreign Ministry. As warfare raged within the former Yugoslavia, he turned chairman of a global panel specializing in bringing peace to Bosnia-Herzegovina.
While he had spent most of his profession as a diplomat, he entered the political fray in 1994, when he was elected as Finland’s President, serving a single six-year time period. A robust supporter of the European Union, he oversaw his nation’s entry into the bloc in 1995, months after Finnish voters had accredited membership in a referendum.
Up till the election marketing campaign, his political popularity had been unsullied. But, as he sought the presidency on behalf of the Social Democratic Party, Mr. Ahtisaari confronted — and denied — critics’ assertions that he had struggled with alcohol abuse and had taken a double wage from the Finnish international ministry and the United Nations for his mediation efforts in Bosnia.
Even as president, he continued as a peacemaker, negotiating to finish combating in Kosovo in 1999.
After he stepped down as president, Mr. Ahtisaari he based the nonprofit Crisis Management Initiative, which helped promote peace within the Indonesian province of Aceh, the place, for 29 years, insurgents from the Free Aceh Movement fought for independence from the federal government in Jakarta.