It’s always an awkward moment when Germans start discussing the war, particularly if the ‘N’ word is mentioned.

The temptation is to respond by issuing bland platitudes designed to send out the correct ‘no hard feelings, water under the bridge, crimes of an earlier generation’ message, and hope that the conversation moves onto less prickly topics, like VD, incest, Gordon Brown. Anything but Nazis, in fact.

Such conversational diversions are not an option when speaking to Ute Lemper, the German nation’s most globally recognised chanteuse since – who? – Marlene Dietrich, probably.

Throughout her 20-year career she has been a fearless champion of the works of the composers and lyricists of the Weimar Republic, particularly those who suffered under the National Socialist regime, and is rightly known not only for her steely beauty but her powerfully visceral interpretations of the songs of Bethold Brecht and Kurt Weill.

But this has not always been an easy gig in Germany itself: “No, a lot of German people still don’t want to be reminded of that time,” she tells me from her home in New York City, “But I think it’s important to tell these stories because, to a new generation, these events seem like a million years ago, but to my generation, it really didn’t happen so long ago at all, especially as time goes by so fast – you know, the Berlin Wall has been down for 20 years already! I was born 20 years after the war into a Germany that was a horror show, basically, with the old Nazis still in their old positions and anti-Semitism still very strong.”

Despite having worked with composers and artists as starry as Michael Nyman, Scott Walker, Nick Cave and Philip Glass, it is with the troubling music of Weimar Germany that Lemper is always most closely associated. Has that ever become a burden to her?

“No. I feel like an ambassador for this music and I’m really grateful to be able to represent it – although I sometimes feel like the last dinosaur doing it sometimes,” she laughs.
“It’s my journey, really as a performer, as a German performer, to have this dialogue, to keep the music alive in a political way, in a philosophical way, in a provocative way. The pre-war period was very interesting artistically until it was shattered totally by the Nazis, so it’s almost been a mission to keep this music, which was mainly written by Jewish composers, alive.”

And despite her family life in the US and having lived in Paris for many years (where she became a noted interpreter of the French chanson tradition) it is Berlin with which she will always be most intimately associated: “I am always going back to those roots,” she says. “There’s always a big piece of Berlin in whatever I do. That’s always my point of departure and my final destination.”

And Berlin is well represented in the program of her Barbican concert, along with her own compositions - by turn wistfully romantic and provocatively political - from recent album Between Yesterday and Tomorrow. So too is the work of the Franco / Belgian chanson school:

“You can definitely compare a Brecht to a Brel,” says Lemper. “They’re both activists, they’re both campaigning, complaining about the neglect of the unprivileged by privileged people. They talk about the forgotten places, the lost souls, you, your neighbour. It’s storytelling, but it’s not fairytale storytelling. It’s…” she struggles momentarily to find the right world before, almost inevitably, settling on one in particular: “It’s political.”