Southern comfort: Fiddlers and box squeezers are heading for Gloucester's Cajun and Zydeco Festival. Roberta Mock does the Jitterbug

I first heard Zydeco performed by some Muppets on Sesame Street. Zydeco is a Z-word, and therefore at a premium for educationalists. From its home in the American swamps, this steamy good-time music with its 'tush-push' dance steps penetrated children's television. It was only a matter of time before it conquered Britain.

Zydeco is a modern derivative of traditional Cajun music, which originated with French settlers in an area of Canada once known as Acadia. Persecuted by British colonialists, most Acadians had migrated to Louisiana by 1765. In the murky bayous they mingled with equally put-upon Scottish and Portuguese settlers, as well as indigenous Americans and African slaves. For nearly 200 years, the Cajun people remained isolated from mainstream America, brewing up a heady culture from eclectic influences.

After a hard week taming the swamps, the Cajuns escaped poverty on a boisterous dance floor. At first they partied to the sound of two or three fiddles, one providing an infectious rhythm, the others playing off each other competitively. Eventually, washboards joined the line-up and later the accordion took over from the backbeat fiddle. Zydeco, a fusion of Cajun and delta blues, added guitars and drums in the 1940s, although it remains accordion-led.

There are four different types of Cajun dance: the western-orientated Jitterbug, the Two-Step to a four-beat waltz, the Three-Step waltz, and Zydeco with its more erotic African influence. I set out to learn the Jitterbug from dance instructors Mary Elms and Amrik Singh.

The Jitterbug resembles the pre-Twist 1950s rock 'n' roll partner dance of the same name. This is not surprising given both are danced to a 12-bar blues beat. 'The emphasis is on eye contact and sticking your bottom out,' Mary tells us. 'Nothing is ever wrong in Cajun dance,' Amrik adds helpfully, 'unless it is painful.'

Amrik, who gives up smoking five hours before dancing, smirks knowingly at our last-gasp cigarette, and warns us that we are going to sweat a lot. He and Mary lead us through gentle warm-up exercises, explaining that 'some people have hurt themselves'. We soon find out how. The basic step, shuffling arouud like a limp chicken, involves the constant stretching of under-developed calf muscles.

Having unconvincingly mastered the 'thinking mode' step, from which all 40 of Jitterbug's increasingly complicated arm movements emanate, it is time to find a partner. I choose Big Dave. We face each other, hold hands, and attempt to bounce up and down at the same time. It takes us a while to establish a rhythm and move forward in unison without my forehead crashing into his chin.

From an inauspicious start we progress rapidly. 'Let's go for a spin,' Amrik calls. Dave and I place hand to hip and just about manage it. 'That's not bad,' says Amrik, 'but the next move involves co-ordination.' The next move is the 'Boston Strangler', or 'Sweaty Armpits', as Mary dubs it.

Dave and I are bursting with confidence, despite the fact that my hair has become tangled up with his watch. We attempt the 'Windmill with Parade' and emerge nauseatingly dizzy. The effect is similar to one experienced after drinking a bottle of Thunderbird. 'You have to maintain eye-contact to establish a steady horizon,' explains Mary. By the end of the session, Dave and I have bonded.

Amrik and Mary were originally taught Cajun dance by Barbara Coppock and Phil Hodgson, who are leading workshops today and tomorrow at the Gloucester Cajun & Zydeco Festival. In addition to workshops in Cajun dance, accordion, fiddle and percussion, the Festival features some of the best Cajun bands in Britain, including The Bearcat Cajun Playboys and R Cajun & The Zydeco Brothers.

'We're living in a globally gloomy time,' says organiser Louis Hawkins. 'This is a chance to stick a few pints down your neck and go wild.' As the Cajuns say: 'Laissez les bon temps rouler.'

Gloucester Cajun & Zydeco Festival, Guildhall Arts Centre, to 16 Jan (0452 505086)

Sat: 12.45pm Bourbon Boys, Baton Rouge pounds 3/pounds 2.50; 8pm R Cajun & the Zydeco Brothers pounds 6/ pounds 5.50

Sun: 12.45pm Eunice and the Red Hot Bayou Band, Joli Blon pounds 3/pounds 2.50; 8pm Bearcat Cajun Playboys pounds 5.50/ pounds 5

Workshops: 3pm Sat Cajun Jitterbug; 3pm Sun Accordion, Fiddle, Guitar, Percussion; 3pm Sun, Two Step, Waltzes

Amrik Singh and Mary Elms run workshops in the south west (0297 625061)

(Photograph omitted)