CECI n’est pas un recital de piano. “Rather,” explains Pascal Roge, one half of the renown piano duo with his wife Ami – they perform at the Perth Festival next week –“we want it to be an experience, an immersion, a kind of portal into the world of Erik Satie et Les Six.”

And what a world that was. Stravinsky called Paris in the 1920s “the hub of the musical universe”. Darius Milhaud, reminiscing years later on the BBC’s Third Programme, described a decade when “everything was possible, we could try everything we wanted. A period of experiment, of liberty in expression in the widest sense of the word.”

This year marks the 150th anniversary of Satie’s birth, and the Roge duo programme puts his music right at the heart of a circle of composers who flourished in no small part because of him.

It is hard not to experience a wee bit of time/place envy when considering this particular epoch. Just think of the personnel involved in the ballet Parade — a sublime work of cubist slapstick which the Roges will perform in Perth in a version for two pianos and which premiered exactly 99 years ago on 18 May 1917. Satie wrote the score and Jean Cocteau wrote the scenario. Picasso designed the sets and costumes and Leonide Massine danced to his own choreography. The impresario Sergei Diaghilev, who commissioned the piece for the Ballets russes, gave his collaborators one strict instruction: “Etonne-moi,” he ordered. “Astonish me.”

On the day of the first performance, Cocteau wrote to the press warning that “laughter is natural to Frenchmen; it is important to keep this in mind and not be afraid to laugh even at this most difficult time.” Parade was a surrealist comedy – bitterly poignant under the surface, but still a controversial piece to produce in the middle of a brutal war. Cocteau later called it “the greatest battle of all”, referring in his own provocative way to an artistic fight to retain humour and joie de vivre despite the odds.

With its bizarre modernism and "noise-making" instruments (milk bottles, typewriters, sirens and fog horns all found their way into in the score), the ballet also signalled a new direction for Parisian musical culture. “Increasingly, we were convinced of its value,” composer Georges Auric later recalled, “and of the lesson Satie was teaching us through it. We used to discuss it every time we met. A current of fresh air had just begun to blow over our little world.”

By "we", Auric meant the group of composers collectively known as Les Six: Francis Poulenc, Darius Milhaud, Arthur Honneger, Germaine Tailleferre, Louis Durey and Auric himself. (Much credit if you were able to name more than three off the top of your head.) This was a new generation, picking up the pieces of a broken French culture and trying to making sense of where to go next. In a city buzzing with musical immigrants – Stravinsky, Prokofiev, Martinu, Enescu, Villa-Lobos, Aaron Copland, Virgil Thomson and George Antheil all made Paris their home in the early 1920s – it’s worth noting that Les Six were an exclusively French consortium. Their concern was in forging a new French style and figuring out what it meant to be a post-war French artist.

Which wasn’t only to do with their experiences of war, although that was a big part of it. It was also about having pointedly nothing to do with Wagner. Around the turn of the 20th century, France experienced Wagnermania along with the rest of the Western world and Claude Debussy was one of the composers intermittently caught in the trance, much to his friend Satie’s dismay. But Debussy died in 1918 and left Ravel, Satie and Les Six the challenge of properly breaking away from the heavy lineage. “A bas Wagner,” came Milhaud’s scandalous cry in 1921: “down with Wagner”.

So what was their new style to be? This is where things become tricky to pinpoint. The programme crafted by Pascal and Ami Rogé for their Perth concert includes Milhaud’s Enfantines, Tailleferre’s Images, Durey’s Carillons, Auric’s Adieu New-York, Honneger’s Pastorale d’ete and Poulenc’s Sonata for Piano Duet – in other words, a range of music that doesn’t share a whole lot of unifying aesthetic qualities at surface level.

Les Six were more a bunch of friends than any kind of explicit artistic faction: it was a critic who gave them their title after a concert in January 1920. They would meet up every Saturday night in a restaurant on the Rue Blanche and amuse themselves late into the night at the funfairs of Montmartre. In his autobiography, My Happy Life, Milhaud writes that the group came about “merely because we knew each other, were good friends and had appeared on the same programmes; quite irrespective of our different temperaments.”

The musicologist Roger Nichols suggests they had a certain technical roughness in common – a roughness that subconsciously demonstrated that they were not in thrall to any academic past. Sure, it jolted with traditional French musical traits of suaveness and cultivation, but that made a key political message “that France was tough, and that her elan vital was undiminished even after four years of appalling slaughter.”

Jean Cocteau – ultimate Parisian aesthete and brazen intellectual egger-onner – was Les Six’s de-facto champion. Poulenc credited him as “our manager of genius; our brilliant spokesman; our poetic chronicler; our loyal and exquisite friend.” And then there was Satie, whom Milhaud called their "mascot".

“Today it is Debussy who is remembered as the great Parisian music genius,” says Pascal Rogé, “but Satie unarguably had more influence.” As John Cage would later assert: “It’s not a question of Satie’s relevance. He’s indispensable.”

Ami Rogé agrees. “Until Satie, everyone was in thrall with Wagner. Then came Satie’s simplicity, clean lines, strange detachment and musical originality. Nobody could begin to guess where he came from, but without Satie the composers of Les Six would not have had the permission to assert themselves as individuals.” There’s something brilliantly Monty Python about it: the unlikely leader, blinkingly decreeing that “you are all individuals.”

What, then, is the common factor in performing this music? Pascal Rogé has made a career of finessing French pianism, but beyond his birthrights – he was born and raised in Paris and studied at the Paris Conservatory with, among others, the great Nadia Boulanger – what does that mean in terms of phrasing, touch, character?

“For me it’s the freedom of interpretation,” he sums up. “This is music that offers many possibilities. It’s about expressing emotion through colour rather than virtuosity. The silences, the ambiguity, the freedom of imagination. The power of suggestion more than spelling things out.”

Pascal and Ami Roge perform the music of Debussy, Ravel, Satie and Les Six at Perth Concert Hall on May 23, part of Perth Festival of the Arts