Washington - In a 180-page missive posted online before the May 14 mass shooting in Buffalo, New York, alleged gunman Payton Gendron wrote that he wanted 'to spread awareness to my fellow whites about the real problems the West is facing.'
The problems, according to the alleged shooter? Mass immigration and white people not having enough babies.
'This crisis of mass immigration and sub-replacement fertility,' the 18-year-old white man wrote, 'is an assault on the European people that, if not combated, will ultimately result in the complete racial and cultural replacement of the European people.'
Though he did not call it by its name, Gendron was referring to a far-right conspiracy theory known as the Great Replacement, which says Western elites, Jews in particular, are bringing in immigrants to replace whites.
In addition to the Buffalo shooting that killed 10 Black people and wounded three others, extremism experts say the racist theory has inspired attacks on ethnic and religious minorities as far away as Christchurch, New Zealand, and El Paso, Texas.
The idea that nonwhite immigrants could eventually displace native-born white Europeans has roots in 20th century French ethnic nationalism. But the term itself was coined and popularized by French white nationalist author Renaud Camus (no relation to Albert Camus).
As he recently told the right-wing outlet Konflikt Magazin, he first came up with the expression in the 1990s in a small, medieval village in the south of France.
There, near 'Gothic windows and Gothic fountains,' were Muslim women in veils and men in djellaba robes, he recalled. 'I was, of course, accustomed like everybody else to seeing the change of people in [the predominantly Arab and Black] suburbs, but there it was especially striking.'
Camus said he later gave a speech titled 'The Great Replacement' in a nearby town, and in 2011, self-published a book of the same title in French.
Though never translated into English, the book helped spur the launch of a trans-European far-right network with connections to extremists in the United States, according to Wendy Via, co-founder and president of the Global Project Against Hate and Extremism.
'The ideas were picked up almost immediately, and they comported with other white supremacist ideas here in the U.S. and other places,' Via said.
Describing it as a 'plain fact' and not a 'theory,' Camus said the great replacement is simply 'a change of people with a change of culture and civilization.'
Extremism experts say it's more than that.
'The great replacement theory is a conspiracy theory that says that white people are purposely being replaced with immigrants, migrants, Muslims, refugees across the world, primarily affecting the Western European countries and the United States,' Via said.
The white replacement idea gained traction in the United States among white supremacists who adopted it as a substitute for their theory about 'white genocide' as they sought to rebrand themselves as white nationalists in recent years.
'The idea of replacing is somewhat easier to understand than genocide for people to accept,' said Michael Edison Hayden, a spokesman for the Southern Poverty Law Center.
Though Camus did not blame Jews, American white supremacists have adopted his phrase as an anti-Jewish slogan.
Many Americans first became familiar with the term in 2017 when alt-right activists organized a rally in Charlottesville, Virginia, where activists chanted, 'You will not replace us,' and 'Jews will not replace us.'
The rally turned deadly when a neo-Nazi sympathizer drove his truck into counter-protesters, killing 32-year-old Heather Heyer.
Link to violence
Camus denies his words have inspired violence. But extremism experts say the replacement idea has helped propel a string of deadly attacks by white supremacists on Jews, Muslims, Hispanics and Blacks in recent years.
Those include the massacre of 13 worshippers at a synagogue in Pittsburgh in 2018; the slaughter in 2019 of 51 Muslims at two mosques in New Zealand; and the mass killing of 23 people, most of whom were Hispanic, at a Walmart store in El Paso, Texas, in 2019.
'It is a substantial influence on these types of attacks,' Hayden said.
Hayden noted that before the replacement idea gained currency in recent years, most mass shootings in the country did not appear to be ideologically motivated. For example, the gunman in the 2012 massacre at a movie theater in Colorado suffered from severe mental illness and had no known extremist beliefs.
Now, shooters have found an ideology to justify violence, Hayden said.
'This functions in almost the same way that terrorists of all kinds are able to find sociopathic people or unstable people and fill them with a sense of purpose,' he said.
In his manifesto, Gendron wrote that the person who 'radicalized' him the most was Brenton Tarrant, the Christchurch mosques shooter whose 2019 massacre manifesto was titled 'The Great Replacement.'
'Brenton started my real research into the problems with immigration and foreigners in our white lands,' Gendron wrote.
Gendron added that he decided to take matters into his own hands after 'learning the truth' on the right-wing message board 4chan that the 'white race is dying out, that Blacks are disproportionately killing whites ... and that the Jews and elites were behind this.'
A Media Matters search of the message board found that users have mentioned the terms 'great replacement,' 'white replacement,' or 'white genocide' more than 90,000 times since July 2018.
Camus has sought to distance himself from the shooting in Buffalo and other attacks allegedly inspired by the great replacement theory.
A Twitter account apparently linked to Camus said Sunday that neither the Buffalo shooter nor the New Zealand mosques attacker had referenced Camus or his book, rejecting the suggestion that his book was a call to hatred or a call to violence.
The replacement idea is no longer confined to the outer edges of the far right. Increasingly, prominent conservative television hosts and politicians have faced accusations of using it as a trope to condemn 'mass immigration.'
FILE - Tucker Carlson, host of 'Tucker Carlson Tonight,' poses for photos in a Fox News Channel studio, in New York, March 2, 2017.
One prominent personality accused of promoting the conspiracy is conservative Fox News host Tucker Carlson. Matt Gertz, a senior fellow at the left-leaning Media Matters, said Carlson started regularly discussing the idea in 2019.
'It was a core white supremacist conspiracy theory that suddenly he was talking about on his Fox News show, and then suddenly, other Fox News hosts were doing the same thing. And then Republican politicians,' Gertz said.
During a segment last year, Carlson said that Biden's policy of 'mass immigration' is designed 'to change the racial mix of the country.'
'In political terms, this policy is called the great replacement - the replacement of legacy Americans with more obedient people from far away countries,' Carlson said.
In comments on Monday night, Carlson said the Buffalo shooter was mentally ill and not politically motivated and that 'the great replacement theory is coming from the left' where activists and politicians push a demographic shift for political advantage.
During a visit to Buffalo to pay tribute to victims of the shooting, President Biden said he condemned 'those who spread the lie' about white replacement. The White House has previously dismissed suggestions that it is promoting an 'open borders' policy.
Other Fox News hosts such as Sean Hannity and Laura Ingraham have charged that Democrats are seeking to bring in immigrants to replace Americans for political gain, according to Gertz.
In the wake of the Buffalo shooting, Republican Congresswoman Elise Stefanik has drawn criticism from Democrats and some Republicans for promoting the racist theory. She has denied the charge.