The year 1989 reshaped the world. Its news stories - from Tiananmen Square to the fall of the Berlin Wall - are now historical landmarks. BBC Diplomatic Editor Brian Hanrahan watched many of the events at first hand, and has been retracing his steps this year to talk to those involved and consider the long-term implications.
It was a baffling year - neither predictable nor inevitable. For those of us in the thick of it, there was a constant struggle to make sense of what we were seeing. Even those with the power to shape events were taken aback. The outcome was not what they had bargained for.
It was a year in which power was transferred away from repressive communist leaders who tolerated no questions or debate about their policies to mass movements which swept away governments and rewrote the map of Europe.
Only China resisted the momentum of change by brutally suppressing demonstrations.
And at times Europe nearly toppled over into mass bloodshed. One night in October I saw East German troops armed and ready to fire on street demonstrators. Only a loss of nerve in the East German politburo prevented a horrendous massacre.
But at the beginning there was little to indicate that we were witnessing the collapse of communism, and the end of the Cold War.
I have looked back through my notebooks and can find not a mention of the round table talks in Poland which began in February and would eventually lead to Eastern Europe's first non-communist government. Few thought it worth remarking on.
The struggle between Poland's communists and the Solidarity movement had been under way for a decade, and from London this looked like another cynical manoeuvre intended to keep the Polish communists in power. That is certainly what the communists intended.
On their own
In London our attention was focused on Afghanistan. The Red Army was abandoning its ill-starred attempt to control the country and retreating. We - the watching diplomats, journalists, and politicians - were trying to interpret what this meant for future Soviet ambitions.
Was it a tactical retreat, or a permanent change of policy?
Brian Hanrahan's original BBC report on the Soviet withdrawal from Afghanistan in February 1989
Fresh from three years living in Russia, I had my own theory. I had seen the depths of the economic crisis on Moscow's streets - poor food, shoddy housing, and roads that would disgrace the third world - and believed this was an empire in decline.
I predicted it would crumble from the edges - a long-drawn-out process that would take many years.
Only in October did the real truth become clearer. With the communists already out of office in Poland, and East Germans fleeing in their tens of thousands through Hungary's newly-opened borders, the Soviet leader, Mikhail Gorbachev, visited East Berlin.
I discovered from West German intelligence that Mr Gorbachev had told the East German leader, Erich Honecker, that the Soviet Army would not back him if he used force against the demonstrators.
How they had access to such a sensitive conversation goodness knows, but the implications were clear.
Brian Hanrahan's original BBC report on Gorbachev's visit to Berlin in October 1989
The Soviet satellites were now on their own. It was a total turnabout from the decades in which Soviet tanks had repressed dissent in East Germany, Hungary and Czechoslovakia.
This was partly because the Soviet Union could no longer afford to support them, but more importantly because Mr Gorbachev believed it unnecessary.
Reformed communism, he thought, would be popular and Stalinist repression was no longer needed at home or abroad.
He was wrong. But his rejection of violence, and moral courage in facing down a hard-line Soviet establishment, ensured the year ended far more peacefully than it might have done.
But how would his client governments respond?
1989: EUROPE'S REVOLUTION
February: Polish government starts round table talks with Solidarity
March: First genuine election in the USSR
May: Hungary removes electrical fencing from border with Austria
June: Solidarity wins Polish election
August: Millions of protesters in Baltic states form human chain to demand autonomy from Moscow
September: Hungary allows East German refugees to cross into Austria
October: Thousands attend peaceful protests in Leipzig
November: Fall of Berlin Wall
December: Romanian dictator Ceausescu executed / dissident Vaclav Havel becomes president of Czechoslovakia
Poland acquiesced and struck the best deal it could with Solidarity.
But East Germany was attracted by the example of China. The communist government there had ruthlessly cut down demonstrators in Tiananmen Square under the eyes of the watching world.
The East German authorities sent a message to New Forum, the group behind the demonstrators.
It said, "Remember Tiananmen". One of my strongest memories of the year is watching the face of Jens Reich, one of New Forum's founders, as he heard it.
Ashen faced, and aware of the enormity of the threat, he said immediately that they would go on.
"We have got to get a dialogue going, so people can say something, before they all disappear. I feel guilty that I have not spoken up sooner."
In the end his bravery, and the courage of millions more like him, faced down communist governments right across Europe. But the dangers were very real and the result in doubt right up until the last.
Every country fought its own battle. No wonder it was a difficult year to make sense of.
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