The door of the Kit Kat Klub bursts open and a man with no clothes on hits the pavement with a slap. He picks himself up, puts on the pair of shoes that followed him out the door, and weaves his way across the street in the direction of the train station. This is not late-night Weimar Berlin, but 11 a.m. on a recent chilly Sunday morning.

The Kit Kat Klub is Berlin's most popular anything-goes sex party, held every weekend at the Metropol Theatre on Berlin's Nollendorfplatz. Around the corner from the Metropol on the Nollendorfstrasse is the house in which author Christopher Isherwood lived in the early 1930s, and where he wrote Goodbye to Berlin, his semi-autobiographical pen sketches of life in the pre-Nazi German capital.

He introduced to the world the talentless Sally Bowles, a character that had a long afterlife in the play I Am a Camera and later in the musical Cabaret as an entertainer in the Kit Kat Klub.

That cabaret never existed, but the fact the Berlin's biggest sex club has appropriated the name shows how the film crystallised the idea of Weimar cabaret as the ultimate den of iniquity.

One hundred years ago this month saw the first performance at the Uberbrettl, Berlin's first cabaret. The small, smoky room with wooden planks for a stage was an inauspicious location, but this first cabaret was a sensation. By the end of the year, over 40 similar venues had opened around the city. Performers discovered to their delight that they could get away with making fun of the Kaiser and of life in the staid, militaristic Prussian capital.

Official censors were too busy vetting "official art" to take any notice and Berlin's upper classes were too busy celebrating 200 years of Prussia to care. A century later, the 100th anniversary of the first cabaret performance in Berlin went by almost as unnoticed as the original performance itself, and for exactly the same reason. Berlin's senate has poured millions into celebrating the 300th anniversary of the foundation of Prussia, but it didn't set aside any funds at all to mark Berlin's first century of cabaret.

In the end, Joanne McNally, a British academic currently living in Berlin, organised a programme of seminars and performances on a shoestring budget, with little or no financial support from the city.

Her greatest interest lies in Berlin's political, satirical cabaret - or "Kabarett" - which she has studied for the last decade. Her 1997 critical study, Creative Misbehaviour, pinpoints two peaks in Berlin Kabarett, both of which occured during the Weimar period.

The first, from 1923 to 1924 was a "creative free-for-all" which took the best talents of the time - and 1920s Berlin was full of talented singers, musicians and poets - and provided them with an audience.

"Take a poet, even a published poet. Their work just sits in a book on a dusty shelf. With Kabarett, poets could perform their works to a receptive audience - every artist's dream," says McNally.

The second peak came in the early 1930s, with two distinct traditions developing. Revue cabarets at the Metropol and the Wintergarten packed in audiences lured by the promise of erotic spectacle. Meanwhile, satirists used their sharpened pencils like switchblades at smaller Kabarett venues like the TingelTangel and the Femina, famous for its table telephones and pneumatic tubes.

Here, composers like Friedrich Hollaender and Mischa Spoliansky turned out songs skewering social conventions and elites such as the newmoney "Smart Set": "We vain myopics take on the great topics/Death and diseases discussed over cheeses/The nature of truth mixed with gin and vermouth. . ."

Writers like Kurt Tucholsky and Erich Weinert wrote sketches and satirical minidramas with what their contemporary Ernst Wichert called "a cool sharp intellect, a cold eye, the capacity for analysis, the incisive knife, the sure hand. There was little that they shunned in the means they used". The intellectuals used the Kabarett to comment on the social problems of the Weimar Republic - high unemployment and rampant inflation - but they could offer few answers. And in the 1933 elections, Germans decided their destiny lay with the National Socialist party.

SOME cabarets carried on into the Nazi period without a break. The venues were popular and, for a time, Nazi chiefs approved of the scantilyclad dancers who "reminded Germans that the healthy Aryan body should be celebrated". But the writing was on the wall.

One official from the propaganda ministry was scandalised by a cabaret's "utilisation of naked women on a very large scale". Another report complained: "Is it not disgraceful for us Aryans, when we allow the appearance of dancers whose costumes lay bare with every movement the charms of woman - a woman who as a German mother should be holy to us, as we have intoned again and again?"

With the second World War looming, many of Berlin's greatest talents fled Germany, most often to the Netherlands and Switzerland. The city's Jewish entertainers, along with the rest of Berlin's Jewish population, were shipped off to concentration camps.

The 1991 documentary Totentanz ("Death Dance") chronicles what is at first glance a bizarre phenomenon: concentration camp cabaret. In the film, survivors of the processing camp at Theresienstadt tell how Monday night cabarets were followed by Tuesday morning shipments of prisoners to Auschwitz and Dachau.

"It seems totally bizarre and unreal to stage cabaret under these circumstances, but people needed the cabaret because they were not dealing with a normal situation," says McNally. "They could still try to be human even if they were being dehumanised."

Political Kabarett survived the Nazis, even if many of its most talented performers did not. It also survived, even flourished, in East Germany, first as agitprop and then as an entertaining voice of freedom.

"We thought we were speaking for the majority of people, because the Kabarett was the only place where you could speak out freely," says Peter Ensikat, artistic director of the Distel, one of the few Kabaretts that has managed to survive.

Performers at the Distel who managed to thrive under censorship in East Germany have learned that satire is only slightly more appreciated in a democracy than it was under communism.

"Some artists think that Kabarett can only exist in a dictatorship," says Ensikat. "We've proven otherwise. I'll do Kabarett under any circumstances."

However, five years after the release of the film Cabaret, Christopher Isherwood, the man whose book started it all, disowned the film and other myths that had grown up around Weimar Berlin. "Wasn't Berlin's famous `decadence' largely a commercial line which Berliners had instinctively developed in their competition with Paris? Paris had long since cornered the straight girl market, so what was left for Berlin to offer its visitors but a masquerade of perversions?" Isherwood wrote.