With coronavirus raging around the world, the pandemic has played to her strengths as a crisis manager with a head for science-based solutions.
Merkel, 66, has said she will step down as chancellor when her current mandate runs out in 2021, and leave politics altogether.
Assuming she finishes out her fourth term, she will tie Helmut Kohl's longevity record for a post-war leader, with an entire generation of young Germans never knowing another person at the top.
Once unthinkable calls for her to stand for yet another mandate can now be heard, however, spurred by her steady handling of the Covid-19 outbreak in Germany, where infection levels and deaths have remained lower than those of most European partners.
The vast majority of Germans say they put great stock in her “hammer and dance” strategy of tighter and looser restrictions based on infection levels, which she this month called “among the most difficult decisions of my time in office”.
The brainy, pragmatic and unflappable Merkel has served for many in recent years as a welcome counter-balance to the big, brash men of global politics, from Donald Trump to Vladimir Putin, as liberals have looked to her as the “leader of the free world”.
A Pew Research Center poll last month showed large majorities in most Western countries having “confidence in Merkel to do the right thing regarding world affairs”.
A trained quantum chemist raised behind the Iron Curtain, Merkel has long been in sync with her change-averse electorate as a guarantor of stability and prosperity.
Her major policy shifts have reflected the wishes of a changing society – among them phasing out nuclear power after the 2011 Fukushima disaster — and shifted her CDU firmly to the political centre.
Before the pandemic her boldest move, keeping open German borders in 2015 to more than one million asylum seekers, seemed set to determine her legacy.
Singer-songwriter Wolf Biermann said Merkel “showed the world the friendly face of human rationality” when she chose not to use “barbed wire, clubs, water cannon, machine guns and tanks to chase away thousands of desperate refugees on the German border”.
While many Germans were on board, the move also emboldened a new far-right party, Alternative for Germany (AfD), which has upended national politics.
At the same time, hardline leaders such as Hungary's Viktor Orban accused her of “moral imperialism” with her welcoming stance.
Five years on, the European Union appears no closer to a unified policy on migration.
Merkel gives a speech in Munich in 2004. Photo: DPA
The woman once known as the “climate chancellor” for pushing renewables also faces a mass movement of young voters pressing her to make Germany meet its own commitments.
She became Europe's go-to leader during the eurozone crisis when Berlin championed swingeing spending cuts in return for international bailout loans for debt-mired countries.
Angry protesters dubbed her Europe's “austerity queen” and caricatured her in Nazi garb.
'Longing for freedom'
Merkel, now the EU's and G7's most senior leader, started as a contemporary of George W. Bush, Tony Blair and Jacques Chirac when she became Germany's youngest and first female chancellor in 2005.
Merkel was born Angela Dorothea Kasner on July 17, 1954 in the port city of Hamburg, the daughter of a Lutheran clergyman and a school teacher.
Her father moved the family to a small-town parish in the communist East at a time when most people were headed the other way.
A top student, she excelled in mathematics and Russian, which has helped her maintain the dialogue with the other veteran on the world stage, Russia's Putin, who was a KGB officer in Dresden when the Berlin Wall fell in 1989.
Merkel kept the name of her first husband, whom she married in 1977 and divorced five years later.
“My heritage shaped me, for example the longing for freedom during my life in the GDR,” she said on the 30th anniversary of reunification.
After the fall of the Berlin Wall, Merkel, who was working in a chemistry lab, joined a pro-democracy group that would merge with Kohl's Christian Democrats.
The Protestant from the east would later be elected leader of a party until then dominated by western Catholic patriarchs.
Now, in turbulent times of multiple global crises, the post-Merkel period looks uncertain.
A leadership battle has dragged on for months, prolonged by the coronavirus outbreak, with the outcome still highly unpredictable.