RFI Music: How did the idea come about to make a musical on the fate of a German revolutionary at the start of the 20th century?
Claire Diterzi: Marcial had the idea of doing Rosa Luxemburg and he thought of me when he saw me on stage playing the music for the show Iris by Philippe Decouflé. He was inspired by the rage and violence in my music. Then I buried myself in her biography and took loads of notes, and several themes stood out for me: the love song, the song about revolution, about her death…

Marcial Di Fonzo Bo: We were really keen to work together. It was a good subject to transpose into Claire’s artist world, and especially through her. I think there’s a pretty special alchemy between the fate of this woman and the questions that Claire asks herself as an artist; things like resistance, revolt and today’s society. We decided to play the music live. Claire with her musicians. No actors on stage or musicians playing actors. The principle of a concert, in fact. That’s how the story was told best.

Was it difficult to compose music based on the biography of a militant communist?
Claire Diterzi: The music was quite easy to compose. But to start with I wasn’t going to do songs. I was thinking of an original soundtrack with four or five songs, but then my record label listened to my demos, which had taken me a year to write, and they couldn’t tell if it was an original soundtrack or a singer’s album. I rolled up my sleeves – it was December 2009 – and shut myself away to compose the missing four songs. I was thinking of a kalash-guitar (Ed.: cross between a Kalashnikov and a guitar) made for the show by the graphic designer Michal Batory, and Marcial had made good progress with the play’s scenography.

Your music flips between electric guitars, electronic rhythms and r’n’b. It’s pretty unusual.
Claire Diterzi: It’s a conscious decision. We didn’t want to get into using rococo pastiche or archived images in the show. The same goes for the music: no retro lyrics or old-fashioned orchestration. I was born 100 years after Rosa Luxemburg, in 1970, but I think the things she said are really topical: resistance and revolution – it’s a good time to talk about them! And I’m not going to sing little songs accompanied by an acoustic guitar for that kind of subject. We needed some sound in there!

The song Je touche la masse is almost an r’n’b number
Claire Diterzi: Rosa Luxemburg spent her days writing or travelling round Poland in trains to go out and meet the working classes. I’m condensing her ideas a bit, but she wanted to reach the people. I drew parallels between her and my own work: I spend most of my time in a truck going to see people, defending my projects and singing them my songs. I don’t sing hits, I wanted to raise a smile with this track that’s a bit like Britney Smears or MTV. The show starts with this one to try and immediately throw things out of kilter. But my lyrics aren’t weak, I was inspired to write them by Rosa Luxemburg’s words: "The world is so beautiful despite all its horrors, and it would be even more beautiful without the cowards and the weak-hearted".

Why did you choose wind instruments and machines to accompany you?
Claire Diterzi: The drums and programming was to throw things out of kilter like I said. All the contemporary bit can be seen on stage. Rosa was obsessed by nature, clouds and birds, and she wrote a lot of letters about them when she was in prison. That’s the reason for the wind instruments, like the horn, which is so majestic. The brass instruments sound like a military fanfare and also like a film soundtrack. The oboe makes you think of birds. I wrote a horn and oboe arrangement for Alain Bashung’s Madame Rêve.

It isn’t really a concert or a theatre play
Marcial Di Fonzo Bo: A bit like music, stage shows often get pigeonholed. This show is a hybrid somewhere between theatre, concert and a video installation. Claire sings, plays and reads Rosa Luxemburg’s words. But I think that it is still a show for the general public, and a really good night out.

After this show, are you tempted to do some acting?
Claire Diterzi: I’d rather die than be an actress! This adds another string to my bow, but I’m still a singer. For me actors are craftspeople, not artists, and they’re often inconsistent and narcissistic. I have much more respect for technicians and creators.