Those elections presented big tests of the bloc’s cohesion. The dispute over Catalonia instead presents a test of the cohesion of a member state itself. And it points to ominous storm clouds in other independent-minded regions, from Scotland to northern Italy.
Catalonia, which has its own language and culture, has long been an uneasy part of Spain, and aspirations for independence have surged and ebbed for generations. But Catalonia is also Spain’s economic engine, and Madrid is determined to hold onto it. The tug of war is now entering perhaps its most intense and unpredictable phase since the approach of the Spanish Civil War last century.
In 2014, the last time Catalonia held an independence vote, it, too, was declared illegal by Spain’s constitutional court. But Catalan officials described that vote as a straw ballot, and the government in Madrid and the police did not prevent it.
This time, sensing the growing seriousness of the Catalan referendum, which the regional government says will now be binding, Madrid is taking a far more aggressive tack.
The approach has left many Catalans bridling under what they say is a heavy hand by the government of Prime Minister Mariano Rajoy. The steps to intimidate people who back a vote not only may backfire, they argue, but also threaten to transform the conflict into a broad campaign of civil disobedience that could spiral out of control.
Tensions on the streets have mounted, along with political recriminations. While the separatists charge that Mr. Rajoy is taking Spain back to the dark days of Franco, Madrid warns that the separatists have shifted from violating Spanish law to encouraging civil strife.
In the interview, Mr. Puigdemont said the conflict would not turn violent, but he warned that Madrid would have to assume its share of the blame if things got further out of hand. “If you stop somebody from unfolding a banner that asks for more democracy, the problem is with the person who forces its withdrawal,” he said.
Even President Trump has weighed in, declaring that he supports a unified Spain after a meeting in Washington with the Prime Minister Rajoy. Mr. Trump took no position on whether the referendum should be held.
The swirl of competing pressures is perhaps nowhere greater than at the local level, among city and small-town mayors who must decide whether to host the voting.
On Monday, Joan Rabasseda, the mayor of Arenys de Munt, headed for a courthouse rather than his town hall because of his decision to ignore Spain’s government and constitutional court and help his residents vote. Mr. Rabasseda could be suspended from office if found guilty of civil disobedience — along with about 750 of the almost 950 mayors of Catalonia who have vowed to facilitate the referendum.
“Spain’s judiciary can go after me, but that’s only helping unite my town even more and increasing everybody’s determination to vote,” Mr. Rabasseda said defiantly.
Catalan officials who do not favor independence say that they, too, are facing intimidation — but from an increasingly aggressive pro-independence movement that wants them to go through with a vote declared illegal by Madrid.
With the referendum just days away, taking a side has become inescapable. In many ways, for Catalonia’s officialdom, it’s a case of be damned if you do and damned if you don’t.
“This conflict is forcing elected officials to walk into a cul-de-sac and then deal with very difficult consequences,” said Irene Rigau, a Catalan politician. “Whatever you do, you will be punished either by your citizenship or by the state.”
Separatist mayors must endorse the referendum, she said, because otherwise “nobody will vote for you again.”
“But if you stick to your promise,” she said, “the state could then never allow you to be a politician again.”
Ms. Rigau was among three senior Catalan government officials who were recently found guilty of civil disobedience for helping coordinate the nonbinding vote on Catalan independence in 2014.
This time, Spain’s judiciary is promising to punish anybody involved in organizing Sunday’s referendum. But for mayors like Mr. Rabasseda, the choice to go ahead with the ballot was simple, if potentially disastrous for him.
His was the first town in Catalonia to hold an independence straw ballot in 2009, at a time when secessionism had far less supporters than it now has. On Monday, a group of about 100 residents escorted their mayor to the courthouse in the nearby city of Mataró and sang the Catalan hymn as he entered the building. When he emerged, they repeatedly shouted, “We will vote!” and “Independence!”
A smaller number of mayors are complaining about suffering harassment and insults for refusing to turn their town hall buildings into polling stations. Their decision is forcing Catalonia’s separatist government to find alternative venues for a referendum whose logistics have already been seriously complicated by the Spanish police, who are seizing ballot papers and other election-related equipment.
While Mr. Rabasseda was in court, Josep Monràs, the mayor of the town of Mollet del Vallès, was filing a police complaint after a group of about 100 separatists surrounded his home last weekend and shouted insults. The protesters used a megaphone and also plastered secessionist posters on his house, Mr. Monràs said in a telephone interview.
He argued that Catalonia “isn’t viable as an independent state,” but that his opposition to the vote was in any case entirely justified by his duties as a Spanish mayor. “Every mayor takes office with a promise that includes respecting the Constitution,” he said.
Mr. Monràs, who has been mayor since 2004, said he had never before received such insults on his doorstep, including people calling him a fascist.
“There have always been people who defend different ideas using legitimate means, but there are now some who use instead coercion and insults,” he said. “It’s outrageous.”
Sunday’s referendum has widespread support in the smaller towns and villages of the Catalan hinterland like Arenys de Munt.
There, the owner of one fish distribution company had plastered a banner showing Josep Lluís Trapero, the head of the autonomous Catalan police force, who has become an icon of the region’s assertion of an independent identity since last month’s terrorist attacks in Barcelona, the region’s capital.
After a foreign journalist left a news briefing, frustrated that it was being held partly in Catalan, Mr. Trapero commented, “Well, very good, well, farewell.” His words have since been turned into a slogan by separatists who want to say the same to Spain.
But support for independence is far more limited in places like L’Hospitalet de Llobregat, the second-largest city in Catalonia, whose mayor, Núria Marín, has been leading the call for mayors not to be intimidated into hosting the referendum.
“I was elected to manage a city, not to provide ballot boxes,” she said in an interview. “Telling me that I should help people vote is a political and not a legal argument — and in this case it’s clearly not one that carries a lot of weight if made before a judge.”
Spain’s attorney general has warned Catalonia’s political leaders that they could be arrested at any time and face criminal charges for misusing public money to finance an illegal referendum.
The separatists, however, have lashed out at Madrid’s efforts to prosecute mayors and eventually, perhaps, thousands of other officials involved in their referendum. They say Mr. Rajoy is returning authoritarianism to Spain.
Mr. Rabasseda, the mayor of Arenys de Munt, said that Madrid’s clampdown has been disproportionate. He was prepared for a court battle, but acknowledged that his legal problems were worrying others, starting with his 86-year-old mother.
“She’s really upset and concerned,” he said. “For her, it’s a bit like returning to the past and the loss of all political freedom.”