Dismissed by critics as a diplomatic dandy, hailed by allies as a creative consensus-builder, Staffan de Mistura takes the hot seat in Geneva on Monday as the man in charge of forging peace in Syria.

In an impeccable suit and pince-nez spectacles, the Swedish-Italian diplomat looks as though he’d be more comfortable strolling through Geneva’s quaint Old Town rather than refereeing a war that has killed more than 250,000 people.

But de Mistura, whose other roles include being Swedish consul on the Italian isle of Capri, has come closer than anyone else to negotiating an end to the Syrian civil war.

The peace talks he mediates resume on Monday, and if they eventually bring an end to the war, it will not be because he forced an agreement, but perhaps because he recognised it was not in his power to do so.

De Mistura took over the job in mid-2014 after the spectacular failure of his two predecessors, Kofi Annan, a former U.N. secretary general, and Lakhdar Brahimi, one of the Arab world’s most accomplished diplomats. Each had quit after holding a peace conference in the Swiss city of Geneva that failed to stop the war.

In contrast to their ambition, he adopted a “minimalistic” approach, removing any expectation that the U.N. could impose peace. He did not summon the warring parties to negotiate, nor order the big powers of the U.N. Security Council to end the war.

That left a leadership vacuum that, late last year, was filled by the United States and Russia. Moscow and Washington used their influence to bring Syria’s warring sides to de Mistura’s table, but it will be up to him to get them talking.

“MY MOTHER WOULD NOT BE DELIGHTED”

In a four-decade diplomatic career that included war zone assignments across Africa, the Balkans, the Middle East and Afghanistan, de Mistura developed a reputation for quietly building trust with warring parties hostile to outsiders.

“I cannot list to you how many people who my mother would not be delighted to know I shook hands with,” he once said.

U.N. spokesman Ahmad Fawzi said de Mistura’s logical approach helps him cut to the thrust of complex issues, and his sense of humour provides relief at difficult moments.

“He has a wonderful way of connecting with people, whether it’s the media or his interlocutors in a difficult political process like this one,” Fawzi said. “When he approaches people it’s with great respect, whoever they are, wherever they are on the hierarchy ladder.” People who have worked with him cite his creativity, evident when he pioneered airdrops to relieve Ethiopia’s famine in the 1980s. Described by the Washington Post as “a loquacious Italian in a safari suit”, he dared the Sudanese People’s Liberation Army to shoot down his rainbow-painted plane.

He was almost shot down again two decades later, as U.N. envoy in Iraq. His plane from Baghdad ran into Iranian war games, and was given 20 seconds to turn around or be destroyed.

He later became the top U.N. man in Afghanistan, and was one of the United Nations’ most experienced diplomats by the time he took on the Syria role, prompting the Guardian newspaper to call him “the man with the toughest job in the world”.

De Mistura, 69, likes to joke that he has a chronic condition, being an incurable optimist. But he also suffers from occasional gaffes. And his start with Syria was not smooth.

“TOO MUCH TIME SUNBATHING”

Rumours abounded that his heart wasn’t in the job and he wanted to do it part-time from Brussels.

He gave an interview to the New York Times, which said he was “more widely known for his dapper style than for any diplomatic coups” and cited a former Lebanese minister as saying he spent too much time sunbathing at a private club.

“I thought it was a little unfair, didn’t you?” de Mistura told Reuters at the time, lining up at the U.N. salad bar.

He angered Syria’s opposition by sounding more open to the views of Damascus than his predecessors had. There followed an almost fatal error, when he told reporters in Vienna that President Bashar al-Assad was “part of the solution”.

He immediately clarified his comments, saying Assad bore part of the responsibility for ending the war. But the mis-step dogged De Mistura for many months and caused deep mistrust.

An early ceasefire plan misfired too, with misplaced hope that a “freeze” in fighting in Aleppo would trigger local truces across the country. When that failed, De Mistura launched open-ended “consultations” with Syrians of all stripes over several months, although opposition armed groups refused to attend.

A political adviser, Mouin Rabbani, quit De Mistura’s team within weeks of arriving, and emerged as a vocal critic, saying he was “out of his depth” and “wasn’t up to the task”.

“The cronyism, dodgy personnel decisions, and resultant amateurism I witnessed were simply breathtaking,” Rabbani wrote of his U.N. experience.

De Mistura’s apparent lack of ambition looked weak but also reflected reality. With Washington and Moscow falling out over Ukraine and Iranian-Saudi tensions in Yemen, any U.N. peace effort would surely have been futile.

Suddenly, by the end of last year, Islamic State (ISIS)’s advance and Europe’s refugee crisis provided stronger motives, a nuclear deal between Western powers and Iran provided an opportunity, and Russia’s entry into the war provided a catalyst. “Geneva 3” was born.

De Mistura, who had been preparing a soft series of “working groups” to debate post-war Syria, was told by the United States and Russia to junk his plans in favour of a legally binding peace negotiation.

He looked in danger of falling into the same trap as Brahimi, whose “Geneva 2” peace talks drowned in a swamp of side-arguments: “Are the opposition terrorists?”, “Can Assad stay in power?”, “Where is the justice for war crimes?” He dodged nimbly, referring the terrorist question back to the U.N. Security Council, leaving Assad’s fate up to the Syrian people, and saying human rights were not negotiatiable. And with no early progress, he halted initial talks last month and told the United States and Russia they needed to do more.

The result was a temporary cessation of hostilities, sponsored by Washington and Moscow and accepted by both Assad’s government and most of his foes.

While far from perfect, the agreement has already quieted the guns in Syria for the first time in five years, providing what could be the first opportunity yet for the warring parties to discuss peace. Perhaps de Mistura’s doubters have indeed been “a little unfair”.