Whose art is it anyway?

The 52nd Venice Biennale is enough to make any British art-lover proud. While Tracey Emin may be the official representative at this Olympics of the contemporary art world, a waterbus ride through the city canals reveals dozens more.

Damien Hirst has brought his New Religion works, shown in London recently, to the Palazzo Pesaro Papafava. Anish Kapoor has a giant new sculpture in steel in the Artempo group show organised by the Belgian collector Axel Vervoordt.

Work by veteran sculptor Anthony Caro can be seen at Venice's Design Art Gallery and another grand old man of British art, Richard Hamilton, is showing A Host of Angels at the Palazzetto Tito. Sarah Lucas and Douglas Gordon have teamed up with international colleagues including the French star Jean-Mark Bustamente for The Hamsterwheel project, which claims to bring together "artists whose work is connected in some cryptic way".

And that is even before you embark on a tour of the national pavilions for the 77 countries - a record - officially participating in the Biennale.

A strong British presence is only to be expected for a nation with a reputation as the hub of the international contemporary art world and its lucrative market. But how useful is it to categorise art by nationality? The world, after all, is quite a different place from the one that established the Biennale in 1895, in an era before mass media and easy travel.

Several artists who have made London their home have made the journey to Italy this year from their native countries. More intriguingly, some artists have adopted entirely new national identities for the purposes of the five-month-long art extravaganza. Most notably, the very British former Turner Prize nominees Sam Taylor-Wood and Mark Titchner are exhibiting in the Ukrainian Pavilion, alongside Juergen Teller, the German photographer who has lived in London for more than 20 years.

"I'm loving being an honorary Ukrainian at the moment," says Taylor-Wood. "So many people keep on coming up to me and asking why."

Just as it is in Britain today, identity is the issue at Venice this year. Emin may be the official representative but a further 11 artists are in town on behalf of Northern Ireland, Wales and Scotland, who have staged go-it-alone shows alongside the "British" entry in recent years. Willie Doherty is Northern Ireland's official artist, Richard Deacon heads the Welsh team while Scotland is fielding six artists including former Beck's Futures' nominees Rosalind Nashashibi and Lucy Skaer.

It certainly raises questions as to what the Biennale is for and which country can really claim victory when Golden Lions, the art fair's top honours, are handed out. And it's not just smaller countries that are muddying the waters of national identity. America has prompted much comment by choosing a dead Cuban, Felix Gonzalez-Torres (who did work and die in New York, it must be said).

Willie Doherty, twice Turner Prize-nominated representative in the Northern Ireland pavilion, says he accepted the invitation partly because it was on behalf of the country where he was born and still lives. He feels that the political situation has meant its artists have been under-recognised internationally. "There was a strong contemporary visual arts scene through the Seventies, Eighties and Nineties, but it was really in the shadow of Britart."

Yet culture in Northern Ireland also has an important function, he says, in tackling questions that he fears are not being addressed by the current peace process and the power-sharing government.

"The subtext of the work I'm showing here, Ghost Story, addresses the deeperseated problems of how we deal with the memory and loss and tragedy of the past 30 years - or some people might say of the last 300 years - of the conflict-in Ireland. That is what the political-process is not dealing with but there is an opportunity of being here in the context of representing Northern Ireland to flag up these issues."

He is not alone in seeing a political imperative in the Venice Biennale. Even a brief amble through the national pavilions suggest the more troubled the recent history of a nation, the more it sees - and uses - culture to examine, reinvent or market itself.

Olga Sviblova, the dynamic blonde curating the Russian pavilion, wants to transform her homeland's reputation with a show financed for the first time by private businessmen as well as the government. Business, she claims, is seeing the point of art for the first time. (She has a track record: Chelsea Football Club owner Roman Abramovich backed her last two exhibitions in London, both at the Gilbert Collection at Somerset House.)

Art is the future," she says. "It's touching that people understand it's important. It's the Olympic Games for contemporary art." The titular work of the Russian pavilion, "Click I Hope", by 25-year-old ex-model Julia Milner, is a glossy interactive exhibit incorporating the words "I hope" in more than 50 languages. It is art as political propaganda just as surely as old Soviet-style sculpture but with a more modern message.

"Everyone thinks that in Russia nothing is working, but now in Russia art works," Sviblova says.

Yet for artists like Titchner coming from London's already thriving art world, that strong sense of nationalism is anachronistic. "The Biennale system is quite odd, with this idea of national presentations. It is an old-fashioned idea - a lot of artists come from one country and work in another. We're fairly diasporic individuals."

When Peter Doroschenko, the American-born, Ukrainian-descended director of the Baltic gallery in Gateshead, was made curator of the Ukrainian pavilion and asked Titchner to take part, the artist asked the same question - why? - as everyone is asking him now.

"But if I was representing the country I grew up in I would have the same problems about nationality," he says. His most provocative contribution is a giant banner proclaiming: "We are Ukrainians. What else matters?"

Doroschenko says he wanted to shake things up a bit by having British alongside Ukrainian artists. "The Biennale is still an interesting concept," he says. "But what is wrong with shaking the tree and seeing whether a good idea comes down?"

Sam Taylor-Wood, whose Ukrainian connection is a ballet dancer she has featured in video works, was intrigued by Doroschenko's thinking. "The whole emphasis on national identity here [in Venice] is quite a big thing. But it's nice to be part of a major international exhibition, and to be in a place where the pressure is off, and not be going through what Tracey is going through."

Not that being in the Ukrainian pavilion in a palazzo on the Grand Canal has proved any less demanding than being in one of the central village of permanent pavilions, such as Britain's, in the Giardini. One of her new works, featuring a swan that had died naturally at a sanctuary, involved some headaches before she was allowed to show it. "We were threatened by a 12th-century law that was tantamount to treason," Taylor-Wood says.

But she still stands by the original idea of an international art competition. "As you come up through the ranks of your career, it's one of the great things to represent your country at the Venice Biennale. It's something that artists do aspire to, but it's a major pressure because every single artist, art dealer, every art gallery from every corner of every obscure part of the world comes here. You really are under intense scrutiny."

Tracey Emin can vouch for that. But she has made clear this week how thrilled she is to be batting for Britain, albeit a modern Britain full of "very, very British" people like her Turkish Cypriot father. And a nationalism which involves dozens of countries showing off their artists is one she is happy to endorse. "It's nationalism at its best possible level."

It may be one for the Government and its concerns for national identity to ponder. It certainly encourages some good old-fashioned cheering for our Tracey come the prize-giving in October. Go girl, go.