Richard Holbrooke: Influential and highly effective diplomat whose finest hour was negotiating the Dayton peace accords

He never achieved his ambition of becoming Secretary of State. But Richard Holbrooke was arguably the most influential and effective American diplomat of his era, admired and detested in almost equal measure, and a central figure in the foreign policy-making of every Democratic administration of the last half century.

Holbrooke cut his teeth as a young US diplomat in Saigon in the mid-1960s, and ended his career as President Obama's special envoy to Afghanistan and Pakistan. But his finest hour came in 1995 when he brokered the Dayton peace accords that ended the Bosnian war.

After two months of exhausting Balkan shuttle diplomacy had secured a ceasefire, Holbrooke brought the Serbian leader Slobodan Milosevic and the presidents of Bosnia and Croatia to the US and sequestered them for 20 days at the Wright-Patterson Air Force base in Dayton, Ohio, virtually holding them hostage until a deal was reached.

The negotiations were "unbelievably difficult," but they succeeded, thanks above all to Holbrooke's drive and ingenuity, and his refusal to take no for an answer. Not for nothing did he earn the nickname of "the Bulldozer". As Henry Kissinger put it, "If Richard asks you for something, just say yes. If you say no, you'll eventually get to yes, but the journey will be very painful."

Dayton was the achievement of which Holbrooke was most proud, and the supreme vindication of his style. Barrel-chested and gregarious, Holbrooke was a diplomatic force of nature. His energy was relentless. He would cajole, threaten, bully, leak and sometimes explode in volcanic rages. He could be vain and jealous – what other diplomat would employ a personal archivist to collect news stories about himself? But he also possessed humour and a massive personal charm.

Often he would drive not just his opposite numbers across the negotiating table but also colleagues, to distraction. However grudgingly, though, almost everyone recognised his ability. "he's the most egotistical bastard I ever met," vice-president Joe Biden reportedly remarked when Obama gave Holbrooke the critically important 'Af-Pak' assignment, "but maybe he's the right guy for the job."

Holbrooke himself had no illusions about the task awaiting him, a challenge he believed that was even greater than Vietnam. "The conflict in Afghanistan will be far more costly and much, much longer than Americans realize," he wrote in The Washington Post in 2008. "This war [then in its seventh year] will eventually become the longest in American history, surpassing even Vietnam."

None the less he threw himself into it with his usual intensity, even though results were patchy at best when he died. His relations with the Afghan president Hamid Karzai were icy, but Holbrooke was no less impatient with US officials he felt did not appreciate the urgency of the moment. They in turn tried to get rid of him, but he survived, thanks on one occasion to the direct intervention of Hillary Clinton – on whose failed White House campaign Holbrooke had worked, and who now held the post he most coveted.

In some respects Richard Holbrooke was a throwback to Averell Harriman and Paul Nitze, those East Coast giants of an earlier generation of foreign policy makers, who also moved easily between Wall Street and Washington. He was born in New York, the son of Jewish immigrants from Europe, attended the Ivy League Brown University, and throughout his life was at home in the salons of Manhattan as the corridors of the State Department.

Almost from the outset a pattern as established. When the Democrats held power, Holbrooke was a public servant. During Republican presidencies, he turned his formidable talents to the private sector – to journalism and writing, and later to consulting and investment banking, which made him a very wealthy man.

Journalism, indeed, was his first love, and only after he had been turned down for a job by The New York Times did he enter the Foreign Service. His first posting in 1963 was to Vietnam, as a field officer in the Mekong Delta. There, Holbrooke was one of a trio of gifted young diplomats who would remain close friends as they later rose close to the summit of power, along with Tony Lake, who became national security adviser under President Bill Clinton, and the Republican-aligned John Negroponte, US envoy to the United Nations in the run-up to the Iraq war, and the first American Ambassador to post-Saddam Baghdad.

After returning to Washington in 1966, he worked on Vietnam at the Johnson White House and became a junior member of the US delegation at the Paris peace talks. He also wrote a chapter of the "Pentagon Papers", the government's secret history of the war whose publication by the Times in 1971 caused huge controversy.

In the Nixon and Ford years that followed, Holbrooke founded and edited Foreign Policy Magazine, a perch that kept him close to the diplomatic world, before being named by the Carter administration as Assistant Secretary for East Asian and Pacific affairs, at the exceptionally early age of 35. During the Reagan and George HW Bush presidencies he returned to New York, helping set up a consulting firm, Public Strategies, that was subsequently bought by Lehman Brothers. But he was never far from the foreign policy fray, and when Bill Clinton won the White House he naturally returned to government, first as US ambassador to Germany and then as assistant secretary for European Affairs, the post that in 1995 would lead to Dayton.

His prestige was at its height, and when Warren Christopher retiredas Secretary of State after Clintonwon re-election in 1996, Holbrooke was widely tipped as a successor. Butthe same abrasiveness and readiness to make enemies that made him soformidable a negotiator probably disqualified him from the job he wanted most, which ultimately went to Madeleine Albright.

Holbrooke never came as close again. He was again viewed as a possible Secretary of State in 2004, only for the Democratic nominee John Kerry to lose the election to George W Bush. Four years later, Hillary Clinton's defeat by Barack Obama similarly dashed his hopes.

Afghanistan and Pakistan, however, were a more than worthy challenge. "If you have a problem that is larger than life," Christopher Hill, another leading US diplomat, commented of his final appointment, "you need someone whose larger than life to deal with it." Richard Holbrooke fitted the bill perfectly.

To the end, he retained a passionate belief in American power as a force for good. That same determination overcame any squeamishness about dealing with the bad guys. Few were worse than Milosevic, the man most responsible for the bestialities in the former Yugoslavia. But "if you can prevent the deaths of people still alive," Holbrooke said, "you're not doing a disservice to those already killed by trying to do so."

Richard Charles Albert Holbrooke, diplomat: born New York City 24 April 1941; joined US Foreign Service 1963; Editor, Foreign Policy Magazine 1972-1977; Assistant Secretary of State for East Asian and Pacific Affairs 1977-1981; US Ambassador to Germany 1993-1994; Assistant Secretary for European and Canadian Affairs 1994-1996; US Ambassador to United Nations 1999-2001; Special US envoy to Pakistan and Afghanistan 2009-2010; married 1964 Larrine Sullivan (marriage dissolved; two sons), 1995 Kati Marton; died Washington DC 13 December 2010.