After Prime Minister David Cameron's speech on the UK's future relationship with Europe, the debate over EU migration to the UK has heated up still further. EU border restrictions will be lifted later this year to allow the free flow of people from Bulgaria and Romania across the continent. It's expected that many will head for the UK.

But there are already tensions over the impact hundreds of thousands of Polish immigrants have had since they moved to Britain after Poland joined the EU in 2004. And this Polish precedent is leading many people to fear a similar "invasion" from Bulgaria and Romania.

"Free us from the shackles of Europe"

One place where there have been protests already, with more planned, is Boston in rural Lincolnshire in the east of England. At a recent demonstration against the number of Eastern Europeans who have moved to Boston, banners read: "No to being European slaves"; "Free us from the shackles of Europe"; "Controlled immigration, not open door invasion"; And "Get back our country."

This small market town has the biggest population of EU immigrants in England. A decade ago almost 99 percent of people here identified as "white British," with the biggest foreign community being 249 Germans. Now one in ten of the population is from the new EU countries, mainly from Poland.

Angelika is just one of those recent Polish immigrants. She arrived in the UK just a few months ago, and only speaks broken English, but she had no trouble getting work in a shop in Boston town centre.

"It's very nice city and more place working," she told DW. "And nice job and nice money [sic]."

Despite the demonstrations, she also thinks that the English are "very friendly". She explains that getting a job was as easy as walking into a shop and asking for work, on her very first day.

Positive integration

Fellow Pole, Szymek has been in England for seven years. He followed his brother to the country and like Angelica was unable to speak good English when he first arrived.

"Accent is very difficult to understand for the person who just like arrived. It's different at school to what it is in reality," he says, describing his first taste of rural England.

Szymek too found a job quickly, within two weeks of arrival, and now works in a hotel. He believes coming to Britain transformed his life.

"There is no real barriers now, you can live wherever you want, you can work wherever you wanna go, and I think it's better that way."

"Stealing our jobs"

Boston is a rural town, and a lot of the Poles who have come here have taken work on the land, something that rankles with locals, who feel they are taking "their" rightful work away, or accepting low-paid salaries. Dean Everitt is a local who has set up the "Boston Protest Group" and is the man behind the recent mass demonstrations against immigration in the town.

"I mean years ago you'd work on the land and for four or five hours work: You'd earn a hundred pounds. Now you're on a basic six pounds an hour, so you can't afford to be going out to do four hours a day. You need to do eight to ten hours work."

He goes on, saying, "They don't need to earn good money, because they all live in shared housing so they can afford to share bills. An English family can't afford do that. The farmers and the supermarkets all push the wage rates down to the minimum of what they can be."

Taking the jobs others don't want

But Dean's views aren't shared by everyone. Duncan Clark is another Bostonian. He told DW, "there is a certain element of jealousy of the itinerant population here in Boston - that these people have come and taken their jobs. They have a better work ethic and they are better educated and the fact of the matter is they work hard and do jobs that other people are reluctant to do."

Some locals might feel that their jobs are being "stolen," but can that assumption be backed up?

Lisa Scullion is a researcher based at the University of Salford. She has been studying the impact of migration into the UK over the past few years.

"From an employer's perspective, in studies where we have spoken to employers, they felt they could more consistently fill some positions, particularly lower skilled, where the conditions might not be fantastic, maybe shift work, food production, picking, packing. They could consistently fill those roles with migrants, better than they could with people from the UK," she told DW.

Britain debates its future in Europe

Recent figures show 7.5 million people in England and Wales were born outside the UK and nearly three million live in households where no adults speak English; so perhaps more dialects and mixes of new types of English will emerge in the future. For some, like Dean Everitt, the issue of immigration is feeding into the debate about the UK's position in Europe in general.

"I think it's time for Britain to protect its borders and close them down and start looking at the fact that immigration now has got to a point where we can't cope, another two years we'll have Bulgarians and Romanians coming in. We already can't cope with the number of Poles we've got, so how are we going to cope with Bulgarians and Romanians? So this country is either going to get ten times worse off, or they need to cap it [immigration]," Everitt said.

Of course the UK is historically a country of immigrants, from the Vikings to the Ugandan Asians, a whole host of different nationalities have settled and integrated into life on these Isles over the centuries, but whether immigration on the scale the UK has seen in recent years is sustainable remains to be seen. For now the residents of Boston, and the rest of the UK can only watch how that integration process works.