It's nice people are seeing how funny the Welsh are,” says Russell T. Davies. “I do think we have a history of being miserable and small and damp on screen. Don't you?”

Not any more. Something has happened to the Welsh. Suddenly, and cheerfully, the principality's sons and daughters are thriving. Two of the UK's favourite TV shows - Davies's babies Doctor Who and Torchwood - are filmed on the streets of Cardiff. A third, Gavin & Stacey, is all about Glamorgan, with Welsh stars, Welsh jokes and a half-Welsh writing team. It won two Baftas on Sunday. And this, after Joe Calzaghe boxed his way through Bernard Hopkins in Las Vegas, after Tom Jones sang Land of Our Fathers from between the ropes.

Much has been written about the Welsh renaissance within Wales - the Millennium Stadium, the Assembly, the film crews on every street corner. And suddenly, it is not just the Welsh who are excited about Wales. It is everybody.

Duffy, the belting Welsh singer (of Mercy and Rockferry), is poised for international superstardom. Hollywood is heaving with Welsh stars, and not just the old warhorses such as Anthony Hopkins and Catherine Zeta-Jones, but a new breed, including Rhys Ifans, Ioan Gruffudd and Michael Sheen. June sees the release of The Edge of Love, a film based on the life of Dylan Thomas (Welsh) starring Matthew Rhys (Welsh), Sienna Miller (has a Welsh boyfriend) and Keira Knightley (not, admittedly, Welsh).

And last month saw the Welsh rugby team winning the Grand Slam for the second time since 2005 and next month Cardiff play in the FA Cup Final for the first time since 1927. Oh, and Lembit Öpik represents a Welsh seat at Westminster. So it's all go.

It was not ever thus. When Anne Robinson famously damned the Welsh in 2002 (“Irritating and annoying,” she told Paul Merton. “What are they for? They are always so pleased with themselves”) the outrage was ludicrous, yet real. MPs fumed in Parliament. The police investigated her under the Race Relations Act and the uproar lasted for weeks. It seemed histrionic then and, in retrospect, it seems absurd.

These days, if somebody makes similar comments, one suspects that the Welsh would either ignore them, or write them into a comedy show. “When you become comfortable,” says Russell T. Davies, “when you start to take the piss, that is when you are actually advancing.”

Davies is from Swansea. He reminds me that Wales is a very small country. “We do lag behind Scotland and Ireland in terms of representation on telly,” he says. “And the only way to conquer that problem is through familiarity. If you see a Scottish or an Irish character in a mainstream drama, they don't stand out. Welsh characters still do. There are so few. Take Gavin & Stacey now. Ruth Jones's voice as Nessa. Brilliant. If you live in Wales, that's a very familiar voice. But I'd never heard it on telly before.”

Gavin & Stacey, if you've been living in a cave, is BBC Three's new runaway Welsh success. As of yesterday, the BBC were making noises about moving it to BBC One. It is written by James Corden (of The History Boys) and Ruth Jones (Daffyd's sidekick from that Little Britain sketch about the only gay in the village) and it is about, pretty much, a love affair between a guy from Essex (played by Matthew Horne) and a girl from Barry (Joanna Page, from Mumbles, the old stomping ground of Catherine Zeta-Jones). Both are blown off screen by the gloriously dirty chemistry between Corden and Jones, but the real star of the show is rural Wales itself, with village surrealism, growling dank, eroticism and characters who speak with the kind of tumbling blunt eloquence that just wouldn't work if their accents were from anywhere else. Rob Brydon, the comedian, plays Stacey's nervous, troubled uncle Bryn. “What it's done is create a version of Wales that's palatable to everyone, something which I don't think anyone's managed before,” he has said. “Along with that, Doctor Who, Torchwood and winning the Grand Slam, I don't think there's ever been a better time to be Welsh since the mid-1970s.”

Peter Gill, the veteran Welsh playwright whose Small Change (set in 1950s Cardiff) is about to appear at the Donmar in London, tells me that Wales has “always had a gift for a certain kind of country & western vulgarity.” The greatest Welsh film never made, he adds, was one starring the young Shirley Bassey and the young Tom Jones. Once, the Welsh might have been embarrassed about their Elvis-loving, teddy-boy edge. Now, maybe, they are revelling in it. A recent episode of Gavin & Stacey saw the whole cast at a barn dance.

It is thanks to Davies, of course, that the whole Welsh televisual renaissance began. In Cardiff, there is talk of a statue. His Doctor Who went there with BBC Wales, as a result of a Beeb directive that more work had to happen outside London. It was such a success that he soon followed it up with Torchwood - a spin-off as strongly wedded to the city as EastEnders is to East London. “The Doctor travels all over the place,” he explains. “So we could only have one Cardiff story every two or three years. Otherwise it would have looked daft.”

Having previously lived in Manchester (where he made Queer as Folk) Davies says that he learnt from Coronation Street how passionate locals could become about a TV show if they considered it their own. And, true enough, Cardiff swiftly went wild for the man from Gallifrey. When required, local authorities seem prepared to virtually shut the city down for filming. In return, Davies has given them busloads of tourists and a budding TV industry, complete with a mammoth training scheme. “When I grew up in Swansea, working in telly simply meant moving to London,” he says. “Now you know for a fact that, if you are 12 in Swansea, you can just go down the motorway.”

Then there is music. The Welsh have been singing for ever (“Have you been to Wales?” Blackadder asked Baldrick, circa 1800, “. . . gangs of tough sinewy men, roaming the valleys terrorising people with their close-harmony singing . . .”) but in the generations since Jones and Bassey, the crooning legends seem to have been piling up on top of each other. I could list them, coming up through the Manic Street Preachers and Stereophonics, right up to the likes of Charlotte Church and Katherine Jenkins, but you might as well do what I did, and just take a look at the Welsh Singers category on Wikipedia. It's enormous.

Leading the pack, suddenly, is the aforementioned Duffy, a 23-year-old blonde soul singer from Nefyn, a predominantly Welsh-speaking spit on the Llyn Peninsula in the northwest. Her debut album Rockferry came out in March. Duffy sings like a creature from another age - nasal in a good way, over a noise like the Wall of Sound. In the hype that now surrounds her, perhaps, we can get a snapshot of what Wales suddenly means to us all. You might think that Duffy has emerged from a time capsule, or that Nefyn, rather than being a slightly eye-watering eight-hour trainride from London, was on the other side of the world. From the reviews to the album cover, Duffy is unspoilt, uncorrupted, vintage, retro, old-school, all that.

There is a lot of this sort of thing going on with Wales. To see Joanna Page arrive at tattered, grey Barry Station in Gavin & Stacey is to sigh with nostalgia, even if you are from nowhere near. Indeed, it might be worth noting that much of the British National Party's lovely hierarchy - including Nick Griffin, the leader, and John Walker, the treasurer - live in various parts of the principality. Could it just be that much of Wales reminds many of us of how the rest of Britain used to be, in simpler, quieter, smaller times?

They won't like that idea in Wales. In March, the Welsh Academy published its first Encyclopaedia of Wales, seeking to produce the exhaustive reference for all things Welsh (reviewers recalled the first entry on Wales in the index of the Encyclopaedia Britannica - “For Wales, See England”) as a testament to an emerging sense of nationhood that is all about history and geography and culture, and suddenly not just about buggering up everybody else's view at rock concerts with flags. The devolved Welsh Assembly may be a poor man's answer to the Scottish Parliament, but as a New Labour project, it may have turned out more according to plan. In Scotland, devolution has bred separatism. Wales seems more British than ever.

As to whether the boom will continue, well that's one for the Welsh. Russell T. Davies suggests that his countrymen have long suffered from an inferiority complex - not just in relation to England, but in relation to more shouty minorities from Scotland and Ireland, too. Perhaps the principality has benefited from their increasing drift away. Peter Gill, however, worries that, although there are Welsh singers, TV stars and sportsmen aplenty, there are fewer writers, poets and composers to match. Even at its most worthy, Cardiff's new Millennium Centre appears to see its role as attracting international talent into Wales, rather than showcasing Welsh talent to the world.

In politics, also, the Welsh continue to punch well below their weight. Whereas the Cabinet is dominated by Scots, the Wikipedia category on Welsh politicians has little of note to say for itself since Neil Kinnock. Indeed, jokes aside, the most tireless champion of all things Welsh in Westminster probably continues to be Lembit Öpik, who has a Welsh seat and was the head of the Welsh Liberal Democrats, but is of Estonian descent and was born in Northern Ireland. “What Wales has to do now is consolidate,” he says. “The worst we can do is languish in our success. The best is bank on it and believe in it.”

Öpik also has little time for any comparisons between the Welsh and other British minorities. “With more than a dozen success stories all at once, you can't cry fluke any more,” he says. “And with the greatest of respect to Scotland, it's not exactly a centre of TV production and it has not had many recent rugby triumphs.”

Dangerous stuff, but a fair point. With sporting successes, pop triumphs and television saturation, it is hard to draw too many parallels between the Welsh and the Scots. And yet, doesn't the Welsh situation ring a bell, particularly as the United Kingdom at large succumbs to their speech patterns? Ah, yes. That's it. Maybe they are the new Australians.

Apart from the people try ...

The Brecon Beacons (and the countryside in general)
Laverbread: Delicious with bacon
The Big Pit: Best interactive museum in the UK
Portmeirion: Has to be seen to be believed
The language: Alive and kicking

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