It hasn't been an uncomplicated period.
There have certainly been issues inside the European Union, but even more important have been the rather fundamental changes in its external environment.
Merkel assumed power when there was still the hope that Europe could build stability by projecting its soft power and its model of shared sovereignty to its neighbourhood and the outside world.
She will leave when protecting Europe from the instability of the surrounding world has become the political priority.
We have seen the rise of a revisionist Russia in the East, a meltdown of the Middle East in the South and a profound disruption in the orientation of the Anglo-Saxon world on both sides of the Atlantic.
But in spite of widespread expectations to the contrary, particularly in the United States, the Greek and the Euro crisis were overcome, and Europe has come out with strengthened rather than weakened institutions after the post-2008 economic crisis. Merkel was a key part of this.
She has held Russia to the fire over its aggression against Ukraine, in spite of some initial rumblings in German business circles and a traditional leftist nostalgia for the old Ostpolitik days, and kept the EU united in its approach. I doubt anyone else could have done it.
She went from having a US president who genuinely liked Germany to one who seems to see her country far more as an enemy than an ally — and she kept her composure.
Her critics will continue to fault her for the refugee crisis of 2015. But the reality was that border controls in Greece imploded, leaving the Balkans open to migrants; Hungary sent them to Austria, and Austria dumped them on the German border.
The real failure was not stopping the war in Syria, or giving the hundred of thousands of refugees in the camps and in Turkey the help and the hope they needed. And many must be blamed for that failure.
Since then, Merkel has been part of the effort to build up our bastions. The refugee deal with Turkey was as controversial as it was essential, and I doubt anyone else could have done it.
And now EU policies across the board are beefed up. For the Chancellor of Germany to head to Niger to help that extremely fragile state manage its migration pressures is also part of the approach.
Her turnaround of energy policies, suddenly abandoning nuclear energy, is widely supported in Germany, but here question marks must remain.
She led the EU in fostering genuine concern over climate change, but she has struggled with Germany's own commitments to reducing greenhouse gas emissions in view of the nuclear phaseout.
The politics of Europe have changed in rather fundamental ways.
The age of ideology has given way to the age of identity, and so we have seen the gradual decline of the large integrating political parties that were so important for stability for decades.
The social democratic parties are mere shadows of their past, and even Merkel's own CDU, still one of the best-performing parties on the continent, is struggling.
Much attention has, rightly, been given to the rise of the far right in Germany and elsewhere in the wake of the immigration crisis of 2015. But if recent trends in different countries are to be believed, its support has now stabilised at well below 20 per cent — with Italy as the exception.
In Germany it looks as though the Greens, with a programme diametrically opposed to the far-right populists, are the rising political force.
But the pattern across Europe is that we see a fragmentation of the political landscape, with governance becoming increasingly complicated.
It took months for Germany to set up the grand coalition government that is now struggling to survive, and when Sweden will get a new government after its early September election is anybody's guess. This is the new pattern of the politics of Europe.
So where are we going now?
We don't know who will take the helm at the CDU in December, and for how long a time that new leader would like to see Merkel remaining as chancellor.
Next northern summer will see important decisions on the leadership positions in the EU, for the next five years, following the May elections to the European Parliament.
I would expect Merkel to be around and to put her imprint on these.
And then a new era will begin.
- Carl Bildt is a former prime minister of Sweden
