LIMA, Peru — Javier Perez de Cuellar, the two-term United Nations secretary-general who brokered a historic cease-fire between Iran and Iraq in 1988 and who in later life came out of retirement to help re-establish democracy in his Peruvian homeland, has died. He was 100.

His son, Francisco Perez de Cuellar, said his father died Wednesday at home of natural causes. Current U.N. Secretary-General Antonio Guterres called the Peruvian diplomat a “personal inspiration.”

“Mr. Perez de Cuellar’s life spanned not only a century but also the entire history of the United Nations, dating back to his participation in the first meeting of the General Assembly in 1946,” said Guterres in a statement late Wednesday.

Perez de Cuellar’s death ends a long diplomatic career that brought him full-circle from his first posting as secretary at the Peruvian embassy in Paris in 1944 to his later job as Peru’s ambassador to France.

When he began his tenure as U.N. secretary-general on Jan. 1, 1982, he was a little-known Peruvian who was a compromise candidate at a time when the United Nations was held in low esteem.

Serving as U.N. undersecretary-general for special political affairs, he emerged as the dark horse candidate in December 1981 after a six-week election deadlock between U.N. chief Kurt Waldheim and Tanzanian Foreign Minister Salim Ahmed Salim.

Once elected, he quickly made his mark.

Disturbed by the United Nations’ dwindling effectiveness, he sought to revitalize the world body’s faulty peacekeeping machinery.

His first step was to “shake the house” with a highly critical report in which he warned: “We are perilously near to a new international anarchy.”

With the 1982 Israeli invasion of Lebanon, and with conflicts raging in Afghanistan and Cambodia and between Iran and Iraq, he complained to the General Assembly that U.N. resolutions “are increasingly defied or ignored by those that feel themselves strong enough to do so.”

“The problem with the United Nations is that either it’s not used or misused by member countries,” he said in an interview at the end of his first year as U.N. secretary general.

During his decade as U.N. chief, Perez de Cuellar would earn a reputation more for diligent, quiet diplomacy than charisma.

“Le ton fait la chanson,” he was fond of saying, meaning that melody is what makes the song and not the loudness of the singer.

“He has an amiable look about him that people mistake for through and through softness,” said an aide, who described him as tough and courageous.

Faced early in his first term with a threatened U.S. cutoff of funds in the event of Israel’s ouster, he worked behind the scenes to stop Arab efforts to deprive the Jewish state of its General Assembly seat. There was muted criticism from the Arab camp that he had given the Americans the right of way in the Middle East.

In dealing with human rights issues, he chose the path of “discreet diplomacy.” He refrained from publicly rebuking Poland for refusing to allow his special representative into the country to investigate allegations of human rights violations during the Warsaw regime’s 1982 crackdown on the Solidarity trade union movement.

In July 1986, Perez de Cuellar underwent a quadruple coronary bypass operation, putting in question his availability for a second term. From the outset, Perez de Cuellar had insisted that he would be a one-term secretary-general.

Upset with what he viewed as member states’ reluctance to pitch in to help the world body out of a financial crisis, he told the New York Times in September 1986, “I don’t see any reason why I should preside over the collapse of the organization.”

But he did come back for a second term after a groundswell of support for his candidacy, including a conversation with President Ronald Reagan, who — in the words of the U.N. chief’s spokesman — expressed “his personal support for the secretary-general.”

“Just about all the Western countries have told him they’d like to see him stay on,” a Western diplomatic source said at the time. “There is no visible alternative.”

Unlike his predecessor, Kurt Waldheim who was regarded as a “workaholic” and who spent long hours in his office, Perez de Cuellar liked to get away from it all. “He is very jealous of his own privacy,” a close aide said.

“When I can, I read everything but United Nations documents,” Perez de Cuellar confided to a reporter. Once on a flight to Moscow, an aide observed that “in the midst of it all, the secretary-general had time for splendid literature.”

Trilingual, Perez de Cuellar read French, English and Spanish literature.

Perez de Cuellar spent much of his second term working behind the scenes on the hostage issue, resulting in the release of Westerners held in Lebanon, including the last and longest held American hostage, journalist Terry Anderson, who was freed Dec. 4, 1991.

All told, Perez de Cuellar’s diplomacy helped bring an end to fighting in Cambodia and the 1980-88 Iran-Iraq war, and the withdrawal of Soviet troops from Afghanistan.

Shortly after midnight on Jan. 1, 1992, he walked out of U.N. headquarters to his waiting limousine, no longer the secretary-general, but having attained his final goal after hours of tough negotiations: a peace pact between the Salvadoran government and leftist rebels.

“Mr. Perez de Cuellar played a crucial role in a number of diplomatic successes — including the independence of Namibia, an end to the Iran-Iraq War, the release of American hostages held in Lebanon, the peace accord in Cambodia and, in his very last days in office, a historic peace agreement in El Salvador,” said Guterres.

Javier Perez de Cuellar was born in Lima on Jan. 19, 1920. His father a “modest businessman,” was an accomplished amateur pianist, according to the former secretary-general. The family traced its roots to the Spanish town of Cuellar, north of Segovia.

In Peru, the family belonged to the educated rather than the landowning class. “He went to the right schools,” a countryman at the United Nations once said of Perez de Cuellar.

He received a law degree from Lima’s Catholic University in 1943 and joined the Peruvian diplomatic service a year later. He would go on to postings in France, Britain, Bolivia and Brazil before returning to Lima in 1961, where he served in a number of high-level ministry posts.

He was ambassador to Switzerland and then became Peru’s first ambassador to the Soviet Union while concurrently accredited to Poland. Other assignments included the post of secretary-general of the Peruvian Foreign Ministry and chief delegate to the United Nations.

After leaving the U.N. Perez de Cuellar made an unsuccessful bid for Peru’s presidency in 1995 against the authoritarian leader Alberto Fujimori, whose 10-year autocratic regime crumbled in November 2000 amid corruption scandals.

At the age of 80, Perez de Cuellar emerged from retirement in Paris and returned to Peru to take on the mantle of foreign minister and cabinet chief for provisional President Valentin Paniagua.

His impeccable democratic credentials lent credibility to an interim government whose mandate was to deliver free and fair elections. Eight months later, newly elected President Alejandro Toledo asked him to serve as Ambassador to France.

Between foreign assignments, he was professor of diplomatic law at the Academia Diplomatica del Peru and of international relations at the Peruvian Academy for Air Warfare.

Transferring to the United Nations in 1975, he was appointed by Waldheim as the secretary-general’s special representative in Cyprus. During his two years on the divided island he helped to promote intercommunal peace talks between Greek and Turkish Cypriots.

After a brief stint as Peru’s ambassador to Venezuela, he returned to the United Nations in 1979 as undersecretary-general for special political affairs. In that capacity, he undertook delicate diplomatic missions to Indochina and Afghanistan.

Perez de Cuellar resigned his U.N. post in May 1981 — just before the election campaign for U.N. secretary-general heated up — and returned to the Peruvian diplomatic service.

However, he encountered political problems at home when he was nominated by President Fernando Belaunde Terry to be ambassador to Brazil.

The nomination failed to win Senate approval. There was no public debate, but congressional sources in Lima said opposition came from Javier Alva Orlandini, Peruvian vice president and leader of the ruling Popular Action Party. The sources said Orlandini resented Perez de Cuellar’s participation in the swearing in of the military junta that overthrew Belaunde Terry in 1968.

Perez de Cuellar maintained that, as secretary-general of the Peruvian foreign ministry at the time, he was required by protocol to take part in the ceremony even though he had no pro-junta leanings.

Belaunde Terry, restored to power in 1980, reaffirmed his confidence in Perez de Cuellar by recommending him for nomination as U.N. secretary-general.

Perez de Cuellar married the former Marcela Temple. He had a son, Francisco, and a daughter, Cristina, by a previous marriage.

His funeral will be held Friday.