Belgium — Member since 1958

Tom Van Grieken

Party leader, national chairman, Vlaams Belang, Vlaams Belang

Tom Van Grieken is the 30-year-old leader of Belgium's far-right Flemish nationalist party, Vlaams Belang, which advocates splitting Belgium into Dutch and French-speaking nations. Campaigning on an anti-immigrant platform, Van Grieken and his party say they want a Flexit — or Flemish exit — if the E.U. fails to listen to their anti-migration message.

Denmark — Member since 1973

Kristian Thulesen Dahl

Leader, Danish People’s Party

Congratulating the British in a Facebook post, the Danish People’s Party leader, Kristian Thulesen Dahl, said, “The EU has taken too much power from the states and is now paying the price.” The DPP opposes the E.U., saying, “We will not allow Denmark to surrender its sovereignty,” but it does support alliances with NATO and the United Nations. Many see Denmark as the next potential departure from the E.U.

France — Member since 1958

Marine Le Pen

President of the National Front; member of the European Parliament, National Front party

President of the National Front party of France, Marine Le Pen has urged France to follow Britain’s lead by holding a referendum on the country’s membership in the E.U. On the campaign trail, she tears into immigrants and Muslims. Polls show Le Pen leading the first round of France’s two-stage presidential election this April and May, but losing in the head-to-head second round.

Germany — Member since 1958

Frauke Petry

Chairwoman, Alternative for Germany party

“The time is ripe for a New Europe,” Frauke Petry of the Alternative for Germany party tweeted. In a response to Brexit, Petry warned the E.U. that more nations will follow the British and “reclaim their sovereignty” if changes are not made. Her party is poised to win big in German parliamentary elections next year.

Hungary — Member since 2004

Viktor Orban

Prime minister of Hungary, Fidesz party

The far-right, anti-immigrant prime minister of Hungary, Viktor Orban, closed the country to refugees last year, exacerbating the crisis. In Britain, “the decisive issue was the question of immigration,” Orban said in a radio interview. “Europe can only be strong if answers are given to the questions of great significance, like immigration, that strengthen it, not weaken it.”

Italy — Member since 1958

Beppe Grillo

Founder, Five Star Movement party

Beppe Grillo, a comedian-turned-politician in Italy who founded the Five Star Movement political party in 2009, has electrified voters fed up with their country’s old-style politicians. A 37-year-old Five Star Movement politician was elected the first female mayor of Rome this year, and another Five Star Movement candidate won the same office in Turin. The party was one of the main opponents of a failed constitutional referendum that led to the resignation of Italian Prime Minister Matteo Renzi. The result emboldened Grillo and his party, which has said that it wants a referendum on leaving the euro.

Netherlands — Member since 1958

Geert Wilders

Founder, Party for Freedom

Founder of the Dutch Party for Freedom, the anti-immigrant Geert Wilders is leading most polls ahead of Dutch elections on March 15. Wilders embraced the Brexit vote and Trump’s victory, telling The Washington Post that Trump “reclaimed democracy for the American people.” But he may struggle to find willing coalition partners in the Netherlands’ fractious political system.

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