The decision came as a surprise.

When the Nobel Committee awarded its annual Peace Prize in 2012, the betting markets had predicted a laureate involved with the Arab Spring. Almost no one expected the prize to go to a fusty institution that had transformed a continent of war to one of peace–the European Union. “War is as old as Europe,” explained Herman Van Rompuy, the first European Council president, accepting the award in Oslo in December that year. “Our continent bears the scars of spears and swords, cannons and guns, trenches and tanks, and more.”

Today, Europe calls to mind bureaucracy. Instead of gunfire and the rattle of tank tracks, the soundtrack to the E.U. is the quiet rustling of papers in the hallways of its capital, Brussels. After the traumas of genocide and upheaval, Europe now embraces compromise. “For this,” Van Rompuy said, “boring politics is only a small price to pay.”

But they’re not so boring lately. One of the world’s most extraordinary experiments in governance–a union throwing together what is now 28 countries with wildly different cultures, to fight around a negotiating table rather than on the battlefield–is under siege from within.

Illustration by Craig Ward for TIME

In the decades after the signing of the Treaty of Rome in 1957, which created the E.U.’s predecessor, glorious blandness came to define Europe. Over time, countries surrendered segments of their governance to a faceless entity that diffuses authority across a handful of confoundingly named institutions: the European Council, the Council of the European Union, the European Parliament and the European Commission.

In his Nobel Peace Prize speech, Van Rompuy referred to the E.U.’s secret weapon as “binding our interests so tightly that war becomes materially impossible.” Those interests range from the common euro currency in 19 countries to frictionless trade and the free movement of people to live and work across the 28 member states. And in the Parliament in Brussels, 751 representatives forge common policies that affect more than 500 million people, on everything from trade and agriculture to technology and the environment. In Brussels, lawmakers make countless decisions about the cars Europeans drive, the food they eat and the pets they own.

It’s an opaque system that most Europeans either struggle to understand or display little interest in trying. Until now there’s been only tepid attention paid to elections for the European Parliament, which take place every five years; in 2014, fewer than 43% of voters even bothered to go to the polls.

This time, the stakes are higher. As the campaign ramps up ahead of parliamentary elections May 23–26, the first Europe-wide vote since an unprecedented wave of migration roiled the continent, Europeans sense they can no longer take their union for granted. Far-right nationalists have banded together in an effort to consolidate their power across the union. Politicians once sidelined as fringe extremists have moved into the mainstream, even if many are still in the opposition. And they are increasingly confident about their chances in May. “With every election in the last three years, in Sweden, Italy, Hungary, Austria, [it is] like dominoes, bing, bing, bing,” Marine Le Pen says, sitting in her office recently in the French Parliament in Paris.

French polls suggest Le Pen’s far-right party–which rebranded last year as National Rally in a bid to shed the image of anti-Semitism and xenophobia associated with its predecessor the National Front–will almost certainly increase its representation in Brussels. Elsewhere, populist and far-right nationalist parties are likely to do well, according to the polls.

Together, they are a long way from claiming the majority in Brussels. But by boosting their numbers in Europe’s Parliament, hard-liners will increasingly be able to shape the debate. That could allow the E.U.’s sharpest critics to begin remaking the union from within–a strategy leaders like Le Pen have spent years planning. Drumming her fingers on her desk, she says, “We are writing history with a big H.”

That history has taken on a different shape in recent months. In the days following Britain’s 2016 vote to leave the E.U.–a major jolt to those raised on a borderless continent–Le Pen decorated her office wall with posters reading, in French, Brexit: and now France! Those “Frexit” posters have now vanished, and there is no exit talk from nationalist politicians like Hungary’s Prime Minister Viktor Orban or Italy’s Deputy Prime Minister Matteo Salvini. Perhaps having witnessed the postreferendum upheaval in Britain, Europe’s nationalists now seem content–or at least resigned–to stay in the E.U., despite their antagonism toward its leaders.

What has replaced a desire to leave, however, could be just as hazardous for Europe: a plan to pick apart the fabric of the E.U., from Brussels itself. “They do not like anything to do with Europe, and they will do anything to destroy it,” says Fabrice Pothier, a former NATO policy-planning director and chief strategy officer at Rasmussen Global, a consultancy firm in Copenhagen. Pothier, who is French, is hoping to stand in the E.U. elections as part of French President Emmanuel Macron’s party. “European solidarity is something that has a very thin veneer.”

Europe’s leaders have never felt more alone. Across the ocean, President Donald Trump has called the E.U. “a foe” of America, stalled a transatlantic trade deal while repeatedly threatening tariffs on European goods, and lashed out at NATO, the West’s cherished postwar project. Former White House strategist Stephen Bannon has crisscrossed Europe, pushing far-right nationalists to wage battle against Brussels. Now a more chilling question looms for Europe’s leaders: whether the E.U. can survive in the long term at all.

Bruno Le Maire, France’s Economy Minister, fears that the challenges to the union could ultimately overwhelm the grand dream that led to its founding. Unless the union can offer the hope that nationalists are promising, he says, “I really do think there is a threat for the European construction to vanish.”

Ex–White House chief strategist Bannon on a rented private plane in Brussels heading to London Cédric Gerbehaye—MAPS for TIME

For some in Europe, a shakeout cannot come soon enough. Facing economic stagnation, uncontrolled migration and intense competition in a tight job market, many see E.U. officials in Brussels as remote technocrats determined to keep the bloc together, no matter the cost. On paper, Europeans’ support for the E.U. is the highest in 35 years, at least according to the union’s own polling data. In reality, that support often seems as undependable as the union itself. From Italy to Austria, millions have voted for populists and nationalists, who attack the E.U.’s core principles and who are plotting to remake Europe from within.

For the E.U.’s defenders, the challenge is how to head off the destructive nationalist impulse the union was formed to combat. “Our darkest angels in Europe are always somewhere under the surface,” says Frans Timmermans, a Dutch center-left politician and the European Commission’s first vice president. In order to keep them at bay, he says, the E.U. will need to “demonstrate that there is some value in acting together as Europeans for the common good.”

If that sounds vague, many in the E.U. say that’s the problem. To them, Brussels is a vast bureaucracy trying to intervene in every aspect of European life, from a distance removed from its harsher realities. Income gaps have widened as Europe slowly recovers from the financial crisis. In 2017, the Paris-based Organisation for Economic Co-operation and Development warned that growing inequality was a political powder keg in Europe and could spur protectionism and populism.

Winning the loyalty of angry, resentful voters will require Europe’s leaders to show they can deliver concrete opportunities. “This is a last-chance election,” says Pothier. “If citizens feel we are not delivering, how are they going to vote next time, in 2024?”

For years, proponents of the E.U. could rely on the fact that their opposition was hardly united. Europe’s far-right and nationalist parties tend to share little beyond concerns about illegal immigration and Islamist-inspired terrorism. Le Pen and her counterparts have been unable to coalesce as a voting bloc, owing to a clash of egos and bitter splits over issues like Russia sanctions and trade policy. That could change in May if they join forces at last. On April 8, Salvini held a summit in Milan with right-wing leaders from Austria and Poland, and he has invited Le Pen and others to the city on May 18 to try to form a political bloc. Europe’s disrupters are trying to coax those big personalities to keep their eyes on a bigger prize: remaking the E.U.

That was Bannon’s message when he opted to throw himself into the European campaign after leaving the White House. Inspired by Trump’s 2016 campaign, Italy’s Salvini–who has met with Bannon twice –has catapulted his anti-immigrant League party to the top of Italy’s polls with the slogan “Italy first!” In July, Bannon flew to London to meet right-wing Belgian politician Mischael Modrikamen. Over lunch in the city’s swanky Brown’s Hotel, the two agreed to form an organization called the Movement, to bring together nationalist leaders across Europe ahead of the May 2019 elections. Bannon then darted around Europe, visiting Orban and other right-wing leaders, as he attempted to knit together a coherent group.

The idea, he told TIME in an interview last fall, was to ready nationalist parties to win in the E.U. elections, through methods like data analytics and polling, honed during Trump’s campaign. “Europe is on fire right now with the populist movement,” he said last summer, sitting in the study of Modrikamen’s Brussels mansion, a large swimming pool gleaming outside the window. He had begun that day in Paris, discussing the strategy for the E.U. elections over breakfast with Le Pen. “The centrist parties do not have the energy,” he said. “They do not have the youth, they do not have the ideas, they do not have the vigor.”

Europe’s politicians hardly need a complete outsider to instruct them in E.U. politics. But Bannon’s strategy of subverting the E.U., rather than leaving it, closely meshes with that of Europe’s nationalists. Salvini and Jaroslaw Kaczynski, the leader of Poland’s ruling party, for example, are discussing how to work together in Brussels. In an interview last fall, Salvini told TIME the aim would be “to re-establish the European spirit that has been betrayed by those who govern this union,” including a severe crackdown on illegal migration and emphasizing Europe’s “Christian-Judeo roots.”

To make a difference in Brussels, the anti-E.U. parties would need to win at least one-third of votes, something that seems possible for the first time in decades, according to some polls. If–and it is a big if–the parties coalesce, they could block key appointments and overrule decisions in a tactic that Bannon described to TIME as “command by negation.” And they could push their own hard-line candidates for key positions, in particular those involved in migration and free trade.

It is those two issues that have riven E.U. politics, beginning with the global financial crisis in 2008. The recession left Greece, Ireland, Portugal and Spain virtually bankrupt, and entirely dependent on bailouts from the International Monetary Fund and the E.U., backed by Germany–Europe’s strongest economy. The loans were often conditional on imposing severe austerity measures that squeezed ordinary citizens and cut public services, deepening a sense of crisis.

“This whole spirit in Europe of ‘we are all in this together’ started to crumble during the economic crisis,” says Judith Sargentini, a Dutch member of the European Parliament, from the GreenLeft party. “And then came the refugee crisis.”

Just as Europe began recovering, millions fled violence in Syria, Afghanistan and parts of Africa. In 2015, about 1.3 million of them endured the dangerous Mediterranean sea crossing and other illicit routes to apply for asylum in Europe, in what became the continent’s biggest migrant flow since World War II.

The refugee crisis was a pivotal moment in Europe, and it set the stage for future divisions. While European leaders fought over how to settle migrants, whether to impose quotas on resettlement programs and the legality of deporting asylum seekers–still unresolved–populists and nationalists seized on the issue as the major rallying cry for their cause. In Germany, where Chancellor Angela Merkel welcomed 1 million asylum seekers, the crisis catapulted the first far-right politicians into the Bundestag for decades.

Britons, on the other hand, have been more concerned about the number of immigrants from poorer E.U. countries. When the E.U. expanded to include 10 mostly Central and Eastern European countries in 2004, the U.K. was one of three nations to immediately open its borders to workers from new member states. In the years before the 2016 referendum, many of those new E.U. citizens moved to the U.K. to work–fueling pro-Brexit voices who argued against free movement in Europe.

Britain was always a hesitant E.U. member, refusing to abandon the British pound for the euro, or to join the Schengen system that eliminates internal border controls between 26 countries. But in several interviews with TIME, top European officials describe Brexit as a seismic, even existential, shock. The first defection by a member state in 62 years has cracked open questions that sputtered to the surface periodically for years, including how to drastically overhaul the E.U., either by limiting its mammoth scope and regulatory oversight or by tightly binding the 27 countries still in it.

Even politicians who fiercely defend the E.U. disagree over what to do. There is the notion of a Europe-wide banking union and financial authority, as well as a European military–proposals pushed by Macron, who has emerged as the E.U.’s most passionate voice. But even among moderates, there is a common view: the E.U. needs to change, and fast. “All over Europe you see the same split,” says France’s Economy Minister Le Maire. “One part benefiting from globalization, and the other suffering from globalization.” Without a drastic fix, nationalism will increase its hold on the continent. “The status quo is not an option,” he says. “The status quo will lead to the end of Europe.”

Italy’s Salvini, right, greets Hungary’s Orban in Milan Marco Bertorello—AFP/Getty Images

The divide goes well beyond the haves and have-nots. It is also a battle between two worldviews: those of the liberal West, which created the common market in the 1950s, and the E.U.’s newer members, many of which are former Soviet satellites where stridently nationalist views prevail. In that sense, Europe’s divide echoes last century’s Cold War, but with the two sides now thrust together in a single union.

The schism has played out most starkly 700 miles east of Brussels–in Hungary, which joined the E.U. in 2004. As such, Prime Minister Orban’s battle with Brussels has become a litmus test for populists and far-right groups across Europe as they edge into the mainstream. At issue is how much they can defy E.U. principles on migration, human rights and economy, while still remaining firmly in Europe’s embrace.

For months, E.U. leaders have railed against Orban, who has been in power since 2010. The most powerful coalition in the European Parliament suspended Orban’s Fidesz party in March, citing his authoritarian policies, such as silencing his critics and driving out of the country the charitable operations of George Soros, the Hungarian-American billionaire who has for decades funded democracy projects in his native country; Orban claims Soros stokes antigovernment activism and illegal migration.

In February, the government launched its E.U. election campaign, plastering thousands of posters on walls across the country, depicting Orban’s two archenemies: Soros and European Commission President Jean-Claude Juncker. You have the right to know what Brussels is planning! the ad screamed from billboards along the airport road and from the pages of magazines and newspapers. It warned of plans like imposing “mandatory resettlement quotas” for migrants and weakening border controls; the E.U. is not implementing either. Many of the posters were covered up in March in advance of a visit by German politician Manfred Weber, who is campaigning to replace Juncker. But for the anti-immigrant government, the message remains in place. “The issue of migration is a game changer,” Hungary’s Foreign Minister Peter Szijjarto tells TIME. “It is the root cause for many of the political conflicts in Europe.”

France’s Le Pen leaves a meeting with Salvini in October Antonio Masiello—Getty Images

Even liberal politicians would agree with that. Migration has become a flash point in Europe’s politics. Though migrant arrivals have dwindled to a tiny fraction from a few years ago, at the peak of the migrant crisis in 2015, more than 400,000 people–mostly from Africa and the Middle East–crossed the Hungarian border in a desperate effort to reach Western Europe. In response, Orban sealed the border with barbed-wire fencing and introduced a law allowing the detention of migrants while their asylum applications are considered.

Szijjarto, the Foreign Minister, says Hungary and its allies in Central Europe like Poland and the Czech Republic are determined to block any moves in the E.U. to make Europe more ethnically diverse. “We would never accept any methods or procedures that would change the composition of the population of the European continent,” he says. “Europe is a Christian continent.” Addressing crowds in Budapest on Hungary’s national holiday on March 15, with Poland’s Prime Minister Mateusz Morawiecki by his side, Orban warned that unless Hungarians resisted the “liberal empire” of the E.U., “Europe will no longer belong to Europeans.”

Orban, who represents fewer than 10 million people, has emerged as one of Europe’s foremost far-right leaders. Having won three straight elections, Orban, 55, is betting his views will have more sway in Brussels after the May vote. “Western Europe is trying to give us political, cultural, all sorts of lessons,” says Orban’s spokesperson Zoltan Kovacs. “We are not going to change.”

But outside of Budapest, among the farmland and small villages, the E.U.’s role looms large. About 22 miles west of the capital lies the picturesque town of Bicske, home to 12,000 people. In March, alongside the anti-E.U. campaign posters featuring Soros and Juncker, were dozens of posters from the E.U. itself. Outside schools, health centers and official buildings there are signposts with blue E.U. flags, emblazoned with its circle of gold stars, listing the amounts European taxpayers have spent on each public project–as they have across Hungary.

The E.U.’s current six-year budget allocates about $28 billion to the country, as part of its assistance to newer, poorer members. Zoltan Tessely, the member of parliament from Bicske and a strong Orban loyalist, says they could not manage without the help. Yet that does not lessen the criticism of the E.U. “Democracy does not work this way, that if you get money you have to keep quiet about injustice,” Tessely says. “Perhaps they believe they have paid for us to shut up.”

But many Hungarians object to their government’s approach. One chilly night in March, activists gathered on the streets in central Budapest to collect signatures for a petition, urging the government to sign on to Europe’s new Public Prosecutor’s Office. They believe that would enable outside scrutiny of Hungary’s affairs and end what they believe is systemic corruption. Akos Hadhazy, an opposition member of Hungary’s parliament and a former member of Orban’s party, says their criticism goes unheard and the government claims the opposition is lying “because they want to bring in migrants.” So why does Orban enjoy huge support at home? “Say a lie enough times, and people will believe it,” he says.

A man sells both Hungarian and E.U. flags in Budapest at a January protest against Orban’s government Chris McGrath—Getty Images

But even in the wealthier, more liberal West, nationalists cast E.U. executives as disconnected elitists out of touch with the concerns of ordinary people. That was the message in northern France one warm Sunday afternoon in late winter, just 80 miles from Brussels, in the small town of Caudry. About 500 people sat in the town’s public hall, clutching French flags and waiting for their idol–Marine Le Pen–to arrive for a campaign rally for the European elections. Onstage, a banner read, Let’s give power to the people.

Two years after Le Pen’s bruising defeat to Macron in the French presidential election runoff, there was a sense among the crowd that their hard-line views–halting immigration and limiting Europe’s borderless trade–might finally have a shot at success in the May vote. Like Orban’s followers, Le Pen’s supporters blame the economic struggle on migrants who have entered Europe; unlike them, they also blame E.U. countries like Hungary and Poland for luring jobs and companies away from high-wage nations like France.

“The E.U. is a laboratory of ultra-liberalism, of free trade, of brutal globalization!” Le Pen told the crowd from the stage, above roaring cheers, and exhorted them to turn the May elections into “a revolt of populism.”

The negative effects of globalization are all too apparent in Caudry. Just down the street from the meeting hall sits the Museum of Lace and Embroidery, a testament to centuries-old artistry and a glimpse into a lost world. Only a few lace factories remain. (Caudry lacemakers stitched Kate Middleton’s gown when she wed Prince William in 2011.) The rest have succumbed to competition from China or lower-cost E.U. countries. Caudry’s unemployment rate is around 27%, according to government statistics–about three times France’s average. In 2017, the decision by U.S. home-appliance company Whirlpool to move its factory from nearby Amiens to cheaper Poland became Le Pen’s rallying cry against the E.U., and Le Pen won many northern areas in her presidential race that year. “About 65% of people in our villages support Marine,” says retired logistics worker Thérèse Marié, sitting in the audience at Le Pen’s rally.

France has also been dealing with the gilets jaunes (Yellow Vests) protests every Saturday since last November, with demonstrators rallying across the country, smashing Paris store and bank windows and burning cars. Sparked by Macron’s imposition of a higher fuel tax in order to pay for an ambitious green-energy rollout, the movement has drawn in many who have never before protested. Several older residents attending Le Pen’s rally in Caudry wore yellow vests. Marié, who says she struggles on her pension of about €1,000 (about $1,130), was defiant: “I am 65, and I’m not even scared.”

More hard-line activists are fighting against an entire system they believe is rigged against them. Victory through chaos, reads graffiti on a wall in Paris. Demonstrators have asked for a rise in the minimum wage and better services in rural areas, as well as the resignation of Macron and his government. To them, 41-year-old Macron–who made his fortune as a Rothschild banker and, as President, has scrapped France’s “wealth tax,” a levy on its richest citizens–epitomizes a cocooned elite that trumpets globalization but cannot grasp the struggles of those left behind. The French President, who has ambitions to succeed Merkel as the unofficial leader of the European project, has been forced to compromise at home. After conducting a three-month listening tour, Macron has promised to introduce sweeping changes. But it has made little difference: the protests have shown no signs of ending.

Left unchecked, economic inequalities may ignite similar protest movements across Europe. Resentments have metastasized over years, from Paris to Budapest–and could take years to resolve. “If you look at European societies since the financial crisis began in 2008, with very, very few exceptions the differences between rich and poor have increased, and sometimes hugely,” says Timmermans, the Commission’s vice president.

So far, populists and nationalists have become adept at harnessing that anger–but few politicians have come up with solutions to quell it. Reflecting on the lessons from months of protests, France’s Le Maire recognizes that “at the heart of the movement is a feeling of economic injustice.” He mentions the American philosopher Francis Fukuyama’s 1989 essay “The End of History?,” which predicted that liberal democracies would govern a more harmonious world. The book made an impact on him. “History is back,” Le Maire says. “History is back with its violence and conflicts.” In May, Europeans will need to decide whether their continent’s long history of fraught nationalism is back too.

This appears in the April 22, 2019 issue of TIME.

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