Its leader, Marine Le Pen, said “The Camp of the Saints,” which she read at 18, “left a great mark on her,” and urged French people to read it to understand what she described as the country’s “migratory submersion.” Steve Bannon claimed that European countries had been confronted with an “invasion” similar to the one described in “The Camp of the Saints.” Iowa Representative Steve King argued that the book’s story “should be imprinted into everyone’s brain.”

In the United States, Beirich said the book stood alongside “The Turner Diaries,” a race war novel by William Pierce, former head of the neo-Nazi group the National Alliance, as the top fictional references for white supremacists. The recognition of the place held by “The Camp of the Saints” in such circles may have reached a new high last week, when it was revealed that Miller, President Trump’s influential immigration adviser, had cited it.

In September 2015, while European countries struggled with an immigration crisis, Miller encouraged Breitbart editors to write about Raspail’s book. Three weeks later, the conservative website ran a story noting that, like in the novel, contemporary Western leaders were “urging on ever larger waves” of immigration, and may well be “unable to erect walls.”

“The Trump administration’s anti-immigration policy is a direct consequence of taking ‘Camp of the Saints’ as a blue book for governing,” Alduy said.

The migrants in “The Camp of the Saints” are portrayed as diseased people who eat human feces — the group’s leader is nicknamed “turd eater” — and their arrival is described as an “endless cascade of human flesh” clambering ashore like an “anthill slashed open.”

Now 94 and a well-traveled monarchist , Raspail seems an unlikely hero to the Americans for whom “globalist” is an insult. Indeed, when “The Camp of the Saints” was published, few could have predicted that the book would have such a wide-ranging afterlife.

The title is taken from the Book of Revelation in the Bible, a reference to the army gathered by Satan who overrun the earth , including the camp of the saints. Raspail drew on his experience documenting endangered communities in Latin America and elsewhere to imagine what waves of outsiders would mean for France’s culture, language and population.