The unforgettable moment a quarter of a century ago when the Berlin Wall came down was the most vivid drama in that dizzying year of revolutions in 1989 when the Soviet empire fell to its knees. But another event a month later and 250 miles away in Prague was equally poignant. As the playwright/philosopher Václav Havel was sworn in as president of Czechoslovakia and declared in one of the most moving speeches I have heard, ‘Citizens, your government has returned to you’, it was clear that if history hadn’t exactly come to an end, the world had changed utterly.

In his own country Havel’s reputation has nosedived since those giddy days, though it flickered briefly after his death two years ago. He is rarely acknowledged nowadays as one of the three great figures — along with Lech Walesa and Mikhail Gorbachev — who played the key roles in the death of communism. Once they were feted in the West. Now, if they are considered at all, they are thought bit players as the Cold War recedes from memory. Perhaps with Russia resurgent and a second cold war looming that will change.

In Havel’s case one can hope that this lively biography will reintroduce a major figure in modern history and letters to a new generation. Michael Zantovsky, the Czech ambassador to Britain, was Havel’s friend and press spokesman during his first years as president. He confesses that he was ‘in love’ with his subject, not always a great qualification for producing an interesting biography. But Zantovsky was an elegant writer before he turned diplomat and this is a clear-eyed portrait that never descends into gush or hagiography.

He describes Havel’s life as a ‘riches to rags to riches fairytale’ — not an exaggeration. Havel was born into privilege. His grandfather made a fortune in land speculation but Havel was 12 when the Communist regime seized the family assets in 1948. As a ‘bourgeois’ he was denied formal education beyond grammar school; he became an awesome autodidact. As Zantovsky shows, Havel was destined, by background and choice, to oppose the Communist state.

In his teens he became a stagehand at a Prague theatre and he started writing plays in his spare time, elliptical and absurdist satires on bureaucracy, which were popular abroad but were never allowed to be staged in Czechoslovakia.

He was better known as an essayist. His great insight, which influenced all dissidents in Eastern Europe, is difficult to explain to people living in a liberal democracy. Under a totalitarian system in which, as Havel put it, ‘the state has an outpost in everyone’s mind’, one effective protest is to bypass officialdom as far as possible. His essay ‘The Power of the Powerless’ was passed round in samizdat everywhere from Brno, to Berlin to Budapest and Bucharest.

From the mid 1970s — after members of one of his favourite rock bands, the Plastic People of the Universe, were arrested — Havel devoted himself increasingly to activism. He wrote endless petitions to the government, among the most hardline in the Eastern bloc, and led every protest group. When in 1979 he described the period since Russian tanks crushed the Prague Spring as ‘the years of forgetting,’ he was jailed for four years.

A handful of dissidents did not bring down the Iron Curtain, though they played a courageous part. A host of factors were involved — the Soviets losing a war in Afghanistan, the fall in oil prices in the 1980s. Nor did Havel look like a charismatic leader. He was short, had an awkward gait and resembled an absent-minded professor. But he had undoubted flair as a revolutionary man of action, unimpeachable moral authority and tactical nous as he negotiated Communism out of power.

Zantovsky’s account of the velvet revolution is masterly. He captures the excitement of the vast demonstrations in central Prague and the high drama of the talks between Havel and the apparatchiks which saw the regime that had lasted 40 years toppled in ten days. Many people wondered what gave Havel, who understood little about administration, the sense that he could lead a revolution. Zantovsky answers: ‘Those who knew him well wondered why anyone would ask such questions.’ He may have appeared otherworldly at times; but people deferred to him.

He is brilliant on personal snippets. We have the last word on Havel’s true musical tastes — he wasn’t the president of rock n’ roll; he liked easy listening. Havel does not emerge as a saint. Zantovsky lists innumerable affairs, one night stands and drunken binges. Invariably he had a maitresse en titre and a casual girlfriend on the go simultaneously. When his long-suffering wife Olga had one dalliance while he was in prison, Havel was unforgiving.

As president, he made a fatal mistake. He stayed on the stage too long. His lasting achievement was to ensure an orderly transition to a genuine democracy — unlike in some other former Soviet bloc countries. On the debit side, as Havel acknowledged, he failed to prevent the velvet divorce between the Czech Republic and Slovakia in 1992.

His aim was to ensure his country ‘returned to the heart of Europe’. If he had retired when the Czech Republic was on the road to membership of Nato and the EU, both popular causes, he could have left office with his dignity intact. Instead he continued for 13 years, ill for long periods, and as Zantovsky reveals in a good scoop, dependent ‘on a variety of drugs …Stilnox (a hypnotic) Paralen, Alnagon (analgesics) Oikamid (a stimulant) and “the white miracle pills for good mood”. He took uppers… he took downers.’ When he finally quit, his popularity was at rock bottom.

Why did he cling on when ‘he didn’t need the office and the office didn’t need him’? Zantovsky offers no answer — one weakness in an otherwise superb book. Havel was not corrupted by power. But it is difficult not to conclude that he was seduced by the belief that he was irreplaceable.

He was the most infuriating of politicians, yet the most beguiling. It was hard to get a straight answer from a man who in the middle of a sentence about the evils of communism would change the subject to the lyrics of John Lennon or ask about the meaning of life — and seem genuinely interested in an answer. And how many in the political world could admit simply that exercising power ‘I appear more and more like an asshole.’ Unlike most others, Havel could fall back on his original career to explain the futility of many political lives.

How wonderful by comparison to be a writer. You write something in a couple of weeks and it is here for the ages. What will remain when the presidents and prime ministers are gone? Some references to them in textbooks, most likely inaccurate.