I learned that the Berlin Wall was falling during an official visit to Poland 10 years ago. On the evening of November 9th, prime minister Tadeusz Mazowiecki invited my delegation to a banquet in the former palace of Prince Radziwill.

Before arriving at dinner, the secretary of the Chancellery, Rudolf Seiters, called from Bonn. He told me that the district chairman of communist East Berlin had suddenly announced temporary regulations permitting travel by private citizens. Permits to visit the West were to be granted to all applicants even on short notice.

With that simple decision, I knew that German history would soon change, for easier travel meant that the Wall was passable for everyone. Still, at first I did not foresee those spectacular and joyous night-time celebrations that were about to take place in Berlin.

Throughout my career I never doubted that Germany would one day regain its unity some time in the future. But I never dared to dream that reunion of East and West would happen during my term as chancellor.

Only with Mikhail Gorbachev and his policies of perestroika and glasnost did reunification become a real possibility. Without Gorbachev and his singular courage, the stream of events across Europe during autumn of 1989 never would have been possible. For with Gorbachev's ascendance, more and more people in East Germany took heart and stopped being afraid of their repressive regime.

They realised that the realities of East Germany were not fixed in stone after all; that it was possible to achieve change, which many brave dissidents and proponents of civil rights trapped behind the wall had demanded for so long a time. Their commitment against the injustice of the communist regime is for me one of the best chapters in German history.

The opening of Hungary's borders that autumn and the seeking of refuge by East German citizens in the German embassies of Prague and Warsaw already had shaken communist and Stasi rule to their foundations. But on the night of November 9th, when the wall and the barbed wire which had failed to divide Germans irrevocably over many decades of bitter separation began to crumble, communism's collapse became irreversible.

We had entered a new era. From that day, the wheel of history spun faster.

When I returned from the banquet to watch the news from Berlin on television, I decided to cut short my visit to Warsaw. It was not easy to persuade my hosts that, at such a historic moment, the place of the German chancellor could only be in our old capital, among the celebrating crowds.

My instincts to return home were also aroused by the scenes that unravelled the next night, November 10th, during a rally in front of Berlin's Town Hall. A mob of extreme leftists succeeded in drowning out the German hymn sung by people celebrating the Wall's approaching collapse.

I was determined to show that the extremists were not representative of Berliners! On the contrary: most people simply felt like expressing feelings of utter joy. They yearned for unity, justice and freedom for their homeland.

So I flew to Berlin, but before I addressed the crowds from the balustrade of Schoneberg's Town Hall, I received a call from Mikhail Gorbachev. The Soviet leader asked me to control public enthusiasm in order to prevent chaos and bloodshed.

He had received reports that the situation was growing out of control. He wanted to know whether it was true that angry mobs were storming Soviet army facilities. One of my staff conveyed my answer to Gorbachev. I assured him that his information was wrong. He believed me.

It helped that we had got to know each other on a human level and to trust each other during his visit to Germany in June 1989.

In spite of differences concerning, for example, the German question, peace for both of us was not just a word but an existential and basic necessity.

Later, Gorbachev told me that he had been intentionally misinformed by opponents of reform who wanted Soviet troops in East Germany to intervene. To this day, I remain thankful to Gorbachev for not listening to agitators but to my arguments.

WHEN faced with the choice of leaving the tanks in their barracks or calling them out on to the streets, he opted for peace and later accepted the new reality that people in East Germany had created with so much courage. For his foresight and bravery, one cannot give him too much credit.

After November 9th the process gained more and more momentum. In an unbelievably short period of only 11 months, German unity became a reality. For me, it was a dream come true. Yet I felt two strong obligations for the future.

One commitment can be loosely described by the image of German and European unity as constituting two sides of the same coin. One could not exist without the other. I expressed the other obligation by talking about the necessity of creating blooming landscapes in the new eastern states of Germany. Both were extraordinarily large and demanding tasks.

In the 10 years since the fall of the wall, I believe that both goals, although not in their entirety, have been reached in their essence. Unified Germany has a strong commitment to both Europe and the transatlantic alliance.

With regard to the new German states, both the transition towards democracy and a free society, and the structural changes made to the former communist economy have been successful, though these tasks will undoubtedly require the energy and labours of several generations before they are completely fulfilled.

Most importantly, Germans regard themselves today as one people, once again. With the help of sound policies, we are poised as a modern society to win the future.