For many French voters, François Fillon is more than a leading contender for president in next year’s elections: He is viewed as a crusader in the throes of a holy war.

When Fillon handily won both rounds of France’s conservative primaries last month, he campaigned mostly on a genteel conservatism of economic restructuring and strengthened national security. But in a country that firmly defines itself as “secular” in its constitution, Fillon’s unexpected victory represented an astonishing prospect: the political reawakening of Catholic France after decades of slumber.

As right-wing and populist leaders across Europe — such as Viktor Orban in Hungary and Marine Le Pen in France — increasingly turn toward Christian values, Fillon has ignited a wave of nostalgia for a nation of traditional families and quaint village churches. It is a nation that he and many of his supporters say is under siege from the dual threats of multiculturalism and Islamist terrorism. As evidence, conservatives cite the slaying of an 85-year-old village priest in July by Islamic State-inspired militants, explaining it as an assault on the essence of France.

Fillon, the presidential nominee of the center-right party now known as the Republicans, has repeatedly pledged to defend “family values” — which has often translated into staunch opposition to same-sex marriage and, lately, to adoption by same-sex parents. When the fervent Roman Catholic responds to terrorist violence, he often does so in the lofty language of religious rapture. The war against the Islamic State, he wrote in his recent book, is “a battle of the end times,” sounded with “trumpets of the apocalypse.”

[Terrorist attack on French church ignites fear of religious culture wars]

People take part in a religious procession, on December 8 in the central French city of Lyon. (JEFF PACHOUD/AFP/Getty Images)

In short, what he promises is a return to his nation’s roots. And in his eyes, those roots are fundamentally Catholic.

Although France is renowned for strict prohibitions on religious displays in public spaces — notably on certain types of veils worn by many Muslim women — it is also a country of some 45,000 Catholic churches and one whose public holidays are almost exclusively Christian in origin. France does not keep statistics on race or religion, but a vast majority of its citizens are said to be either practicing Catholics or agnostics from Catholic backgrounds.

Some insist that France would not exist without the Catholic Church: The nation’s oft-invoked creation myth begins, after all, with the baptism of Clovis I, who united the kingdom of the Franks in the 6th century. And if the French Revolution of 1789 sought to banish religion from public life, it never eradicated religion from private life.

“We have a secular state but not a secular society,” said Matthieu Rougé, pastor of Paris’s St. Ferdinand des Ternes Catholic Church and an expert in political theology.

“The majority of the French are recognized as cultural Catholics. They may have studied in a Catholic school, they marry in churches, and they baptize their children. They are Catholic,” he said. “All our streets, the names of our towns and villages — everything is related in some way to the Catholic faith.”

In provincial towns like Chartres — and in Fillon’s native northwest region — that ancient relationship is apparent everywhere. Anchored by a majestic medieval cathedral, Chartres is home to a relic said to be the tunic that the Virgin Mary wore at the birth of Jesus. In a country where a majority of the public opposed the “burkini” on grounds that it violated secular values, this fragment of cloth draws thousands of pilgrims every year.

Voters in Chartres said Fillon appealed to them because he defended Catholic virtues that, in their eyes, France has forgotten as it has evolved into an increasingly diverse and cosmopolitan society.

“Mr. Fillon is a true Catholic, a man of tradition and rooted to the place he is from,” said Odile Steinmetz, 82, a retiree and practicing Catholic, who voted for him in both of the primary rounds.

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Philippe and Sandrine Mathieu, 51 and 41, respectively, work in a framing shop near Chartres Cathedral. Although they described themselves as non-practicing Catholics, both said Fillon’s Catholic identity appealed to them at least as much as their perception of his seriousness.

“For 20, 30 years, there’s no social cohesion in France,” said Philippe Mathieu. “We’ve lost our values.”

Asked to define these values, Sandrine Mathieu explained that they had sent their children to local Catholic schools instead of public schools because “there they say, ‘Bonjour, madame.’ ”

These sentiments, analysts say, suggest the emergence of a new French conservatism increasingly focused on the concept of patrimony, an amorphous sense of cultural inheritance largely unrelated to matters of policy or the economy.

“These voters consider themselves as legitimate defenders,” said Denis Pelletier, a historian who specializes in Catholicism. “They are defending France. There is economic liberalism there, but mostly there are traditional family values, authority and a sense of the moral order.”

Members of the clergy explain this increasing embrace of religion in the context of recent terrorist attacks, which they say have drawn many secular French Catholics back into churches for the first time in years.

“In a moment of uncertainty,” said Pierre Durieux, an official in the Catholic diocese of Lyon, “the Christian faith becomes a source of solace for so many. The church is a community that allows people to continue to explore their strong emotions, confront their fears, through ritual and prayer.”

For Steinmetz in Chartres, the church is the last line of defense in France’s war on terrorism.

“With Daesh,” she said, using an alternate name for the Islamic State, “we have to take back our country and guard its Catholic values. Because they want to kill us all.”

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