Hailed as a straight-talking politician, the Social Democrat has earned the respect of troops and voters for his efforts to strengthen the Bundeswehr, Germany's armed forces, and support Ukraine in its fight against Russia.

That saved his seat at the cabinet table when conservative Friedrich Merz officially took over as chancellor Tuesday from Olaf Scholz of the centre-left Social Democrats (SPD).

The SPD -- staying on as a junior partner to Merz's CDU/CSU alliance -- decided that Pistorius would remain in charge of Germany's defence ministry, a job he has held for over two years.

Pistorius, 65, now has at his disposal an unprecedented budget to make the armed forces battle-ready in the face of sabre-rattling from Moscow and an uncertain future for the transatlantic alliance.

The new government intends to borrow hundreds of billions of euros to upgrade the military after years of underinvestment in the post-Cold War era which has drawn the ire of US President Donald Trump.

Pistorius took the job in January 2023, as Berlin stepped up arms shipments to Ukraine, making Germany the country's second biggest military backer after the United States.

In a job that has derailed many politicians before him, he quickly became Germany's most popular politician according to opinion polls, a position he has maintained ever since.

Under Pistorius, Berlin also decided to deploy a German brigade to Lithuania by 2027 to help strengthen NATO's eastern flank.

- 'Red general' -

Born in the northern city of Osnabrueck on March 14, 1960, Pistorius completed his own compulsory military service in the early 1980s.

He went on to study law and work as an attorney before entering politics in the 1990s.

He became mayor of his hometown and later interior minister of Lower Saxony state, where he gained a reputation for his work in renewing the police force and boosting it to combat extremism.

When Pistorius became defence minister, Der Spiegel news magazine nicknamed him the "red general" for the colour of the centre left Social Democrats party and his hard-charging style.

"Pistorius is considered impatient, occasionally comes across as brash and can sometimes barely conceal it when he is annoyed with others," public broadcaster NDR wrote of him.

As Scholz's unwieldy three-party government engaged in open bickering last year over fiscal and economic policy, Pistorius stayed above the fray.

After Scholz's government came crashing down in November, some voices within the SPD begged Pistorius to take the helm to try to turn around its dire poll ratings.

But Pistorius refused to make a move for the party crown and played the loyal soldier, backing Scholz.

As the SPD went down to its worst defeat in history, with around 16 percent of the vote, Pistorius is now the last man standing from the old ministerial lineup.

He has two daughters and was widowed in 2015 when his wife died of cancer. He remarried in December 2023 to academic Julia Schwanholz.