It was a movement fully embraced by shooter Wade Michael Page.
With a shaved head and tattoos, Page played guitar and sang for a number of white power bands with names like End Apathy and Definite Hate, espousing views on albums such as "Violent Victory" and encouraging others to act through his Internet postings.
"Violence is part of this culture," said Robert Futrell, professor of sociology at the University of Nevada, Las Vegas, and co-author of American Swastika: Inside the White Power Movement's Hidden Spaces of Hate.
Called "hate music" by detractors and "independent music" by advocates, it provides an outlet for white supremacists, some of whom openly preach violence against minorities while others offer more subtle messages of angst and alienation found in many forms of music.
"There is a set of ideas that suggests that a race war is going to happen," Futrell said, in which whites will be pitted against all others and must fight to defend against their extinction.
"Part of preparing for the race war is stockpiling weapons," he said. "It's instructive to know that one of (Page's) bands was called 'End Apathy' and part of this ... is this push to activate people. So his action could be seen as an act that sparks or catalyses action, that sparks or ends the apathy he was seeing."
Former white supremacist Arno Michaels, the founder of Life After Hate, an online magazine that advocates for racial, religious and gender equality, said white power music was "an active practice of hate and violence."
"If you are playing white power music ... you are learning how to hate people and you are practicing emotional violence against them. Tragically, what happened on Sunday was the logical conclusion of this hate and violence," Michaels said.
Armed with a 9mm handgun, Page, a 40-year-old US Army veteran, opened fire at the Sikh Temple of Wisconsin, killing six people and wounding four others before he was shot dead by police.
The dead were five men and one woman, aged between 39 and 84, including the president of the congregation and a priest.
Police were searching for a motive, but the New York-based Sikh Coalition said it believes Page was driven by hate. The shooter also left a number of clues in his music and postings on Internet site for skinheads.
VIOLENT THEMES
The Definite Hate album "Violent Victory" displayed a drawing of a white arm punching a black man in the face, one eye popping out of its socket and blood coming from his mouth.
Page was also closely tied to the Hammerskin Nation, a skinhead organisation whose 14-word motto - "We must secure the existence of our people and a future for white children" - has made the Roman numeral 14 a symbol of the movement.
The neo-Nazi skinhead group is deeply connected to the white power music scene with chapters across the United States and in Europe, New Zealand and Australia. The group puts on one of the biggest white power music festivals, called Hammerfest.
Page's most popular song, "Self Destruct," carried no overtly racial message. But other songs he played on, such as "Backbone," openly preached white supremacy with messages such as, "It's 2010 and here we are to get rid of them; The enemies of the white race."
"Gather your guns, the time is now," says another line in the song.
The Definite Hate song "Take Action" was even more direct.
"All the talking is done and now it's time to walk the walk; Revolution's in the air, 9mm in my hand. You can run but you can't hide from this master plan."
The record label that released works by Page's band End Apathy, Label 56, removed all images and products related to End Apathy and issued a statement expressing sympathy for the victims.
"We do not wish to profit from this tragedy financially or with publicity," Label 56 said. "In closing please do not take what Wade did as honorable or respectable and please do not think we are all like that."
Page emptied several magazines at the temple in Oak Park, Wisconsin, and several more unused magazines were found on the scene.
He was discharged from the Army in 1998 after six years of service for "patterns of misconduct," according to military sources. In June 1998, he was disciplined for being drunk on duty and had his rank reduced to specialist from sergeant. He was not eligible to re-enlist.
The Anti-Defamation League, which tracks white supremacists in the United States, identified Page in 2010 when it noticed End Apathy and Definite Hate were performing at several music events organized by well-known white supremacists, said Mark Pitcavage, director of investigative research for the league.
Pitcavage said white power music is modeled after three main genres, Oi, a British subgenre of punk rock; punk rock, and black metal.
There are between 100 and 150 white power music groups in the United States at any given time, he said.
"There's a chicken or egg question there. Is it hate music that motivates some of these people to violence or is it that they already have this mindset?" Pitcavage said.
According to the SITE Monitoring Service, a Maryland-based firm that tracks extremists on the Internet, Page was a "strident member" of the forums he joined and had posted hundreds of messages on websites, agitating for white supremacist actions.
In recent days, Page turned from his guitar to a gun.
On July 28, he walked into The Shooters Shop in the Milwaukee suburb West Allis, and bought a Springfield Armory XDM for $US686.39, said store manager Eric Grabowski.
He came back two days later, after the 48-hour background check cleared, to pick up the gun and spent 20 minutes practicing in the gun range in the basement, Grabowski said as the practice rounds from other shooters could be felt through the floor.
"Nothing stood out about him. The people we remember are the ones who rub us the wrong way. If something stands out, we deny them a sale," Grabowski said.
"My heart goes out to the families. My first thought when I heard the news on Sunday was, 'God, I hope I didn't sell him that gun.'"
