For a footloose generation of Poles, home increasingly means Britain or Ireland. In the three years since Poland joined the EU, millions of Poles have joined a westward exodus, with these two countries as clear favorites. By some reckonings, Ireland now plays host to 200,000 Polish ex-pats—equivalent to 5 percent of the population—while Britain accommodates at least 700,000. By contrast, Spain (population: 40 million), another leading magnet for Poles, has pulled in a mere 150,000. France has been issuing barely 10,000 work permits to Polish citizens. While the mass influx of Eastern Europeans has stirred controversy across Western Europe, it is largely a move of Poles to the British Isles, where they are reshaping culture from politics to schools, media to pub life.

Behind this new Polish connection: Britain and Ireland’s warm invitation. When Poland and nine other countries joined the EU in 2004, current members were given the right to delay opening their labor markets to job seekers from the East. Big countries like France and Germany kept their doors shut. But Britain and Ireland threw them wide open, perhaps not quite realizing what they had done. Government experts predicted just 13,000 migrants would come in annually from the new member states. Some from every country took the bait. Others stayed put. Slovenia’s economy was strong. Hungarians have little tradition of emigration. Czechs and Slovaks tended to look for jobs closer to home. But tens of thousands of Latvians and Lithuanians moved across the continent. And Poles responded in record numbers, creating the largest in-migrations in recent British history.

With a population of 39 million, Poland is by far the largest of the new EU members, and it also has a tradition of migration. Facing double-digit unemployment back home, Poles were drawn to Britain and Ireland by strong job prospects in two of Europe’s top-performing economies, by the chance to learn English and by budget airlines that slashed the cost of travel. British forecasters were wrong again when they predicted that most newcomers would stay only long enough to make some money. A survey this summer found that roughly half the new Polish migrants had no intention of leaving.

Now Britain is pondering its new life with a permanent Polish minority. Unlike other migrant groups, the Poles spread out across Britain, often ignoring the allure and expense of the big cities. Polish can be heard in the shipyards of northeastern England, the raspberry fields of Scotland and the meatpacking plants of western Wales. Some areas of Britain now display road signs in English and Polish. At least one police force gives officers prompt cards with Polish translations of vital phrases. In Ireland, Polish priests have restocked the ranks of the Roman Catholic clergy, and Polish barmen staff the pubs in rural areas. The smartest are already climbing the employment ladder. “At first people were just grabbing any job they could get,” says Bartek Wasiewski, a London shipping agent who arrived in 2004. Now some who had started out on construction sites have moved into financial jobs or set up their own companies.

With greater affluence comes attention. The largest British supermarket chain, Tesco, now stocks a range of Polish food. The giant Borders bookshop chain offers more than 100 titles in Polish. British pubs sell Polish lager on tap. The Polish-language media include a daily, four weekly magazines and five radio stations. This month a Polish university plans to open a London branch.

Some British authorities complain of a strain on public housing, health services and schooling. But the path has been smooth for most Poles, in part because they have come at a time when key blue-collar skills are in short supply. John Holdich, an official in the English city of Peterborough, where Poles account for as much as 10 percent of the population, says the city’s two new schools probably could not have been built without the Poles. The political connection is growing, too, and it’s not just Polish leaders who are courting Poles in the British Isles. Before Scotland’s parliamentary election earlier this year, the Scottish National Party published leaflets in Polish. And with London’s local elections due next May, Mayor Ken Livingstone this summer entertained about 100 representatives of the Polish community at a city-hall reception. On the menu: pierogi and red cabbage. Why go home when so much of Poland is in Britain?