The deluded theories that spread poison around the globe - the sort believed by arsonists who torch Irish refugee centres
The suspected shooter claimed he was just one of "millions" of people holding the beliefs that inspired the massacre of 50 people.
Brenton Tarrant claimed only Anders Breivik's Knights Templar group knew of his plan - but said he had "donated to many nationalist groups and interacted with many more". He claimed he decided to carry out an attack two years ago, while on holiday travelling in western Europe in early 2017.
Security sources have said Tarrant may have met extreme right-wing organisations during his visit, which coincided with increased tensions over Isil-inspired terror attacks and the French presidential election. His "manifesto" was posted to messaging board 8chan with a plea for anonymous users to spread his message around the world, and they did.
But nothing in the 16,000-word document is new - the ideas, ideologies and memes used have long been spread by far-right groups and figures across the US, UK, Australia and Europe. Tarrant has also expressed his belief in the white genocide conspiracy theory, which states that white people are being "replaced" by non-whites in western nations. He used the so-called 14 words at the core of the theory in his manifesto.
The phrase - "we must secure the existence of our people and a future for white children" - has been appropriated by far-right terrorists around the world, including possibly the arsonists behind the fires in Irish refugee centres. But there are many other proponents of the white genocide conspiracy. Donald Trump drew attention to the theory in 2016, when he re-tweeted a post by a racist and anti-Semitic account called "WhiteGenocideTM".
An alternative version of the same theory, called "the great replacement", is spread by the pan-European ethno-nationalist group Generation Identity and it was chosen by Tarrant as the title of his document.
Demographic change in Europe and debate about how migrants should be integrated has been seized on by the far right and driven a surge in support for populist parties in recent years. Many extremist groups use birth rate statistics to claim white people are threatened in Europe, but "white" ethnicity is ill-defined.
The claims were a recurrent theme of Tarrant's screed, which called for white people to kill non-white and Muslim "invaders" and have more children. Tarrant claimed he had "brief contact" with Breivik, whose own manifesto has inspired attackers and plotters including a US Coast Guard officer who plotted to kill Democrats and journalists.
He claimed he then told Breivik's followers, who call themselves the Knights Templar, of his planned attack and received their "blessing". It is unclear whether contact between Tarrant and Breivik would have been possible. Norwegian authorities have said the computer the mass murderer is allowed has no internet access, and phone conversations are allowed only with a "female friend".
Breivik massacred 77 people in the 2011 attacks targeting the Norwegian government and young Labour Party members.
Tarrant denied being a Nazi but called himself a "fascist" and used neo-Nazi motifs including the Odin Cross and "black sun", which was featured on the front page of his manifesto. The document was mainly formatted as a Q&A, where he asked himself: "From where did you receive/research/develop your beliefs?" The reply: "The internet, of course. You will not find the truth anywhere else."
Robert Evans, of internet research group Bellingcat, cautioned Tarrant's manifesto may itself be a form of "shitposting", where ironic or false content is used to provoke a response.
"The entire manifesto is dotted, liberally, with references to memes and internet in-jokes that only the extremely online would get," he wrote. "They are meant to distract attention from his more honest points, and to draw the attention of his real intended audience."
Amid condemnation from mainstream figures, prominent YouTubers claimed the atrocity was being used to attack their platforms - and the darker forums where Tarrant sourced his views continued to defend them. On Gab, which styles itself as a "free speech social network", many far-right users were justifying the attack by claiming the suspect was merely "fighting back" and "resisting invasion".
On 8chan, where one user hailed Tarrant as "the next Breivik", anonymous users were openly celebrating the massacre. Mr Evans wrote: "Before much more than an hour had passed, there were already calls for other anons to follow in his bloody footsteps."