Oslo Suspect Cultivated Parallel Life to Disguise ‘Martyrdom Operation’

When Anders Behring Breivik was not plotting mass murder and fine-tuning the bomb he detonated here last week, he was busy playing video games and blogging, listening to Euro pop and watching episodes of “True Blood” — except on Sunday nights, when he usually dined with his mother.

It was a parallel life he maintained meticulously in recent years. Former classmates and colleagues described him as unremarkable and easy to forget, qualities, perhaps inborn, that he cultivated — consciously, he would say — to mask his dedication to what he called his “martyrdom operation.”

For years, Mr. Breivik, who is 32, participated in debates in Internet forums on the dangers of Islam and immigration. It is not clear at what point he decided that violence was the solution to the ills he believed were tearing European civilization asunder. Before the attacks that he has admitted mounting on government buildings and a children’s summer camp on Friday, he was careful never to telegraph his intentions.

“He didn’t say anything you could remember,” said Stig Fjellskaalnes, who knew Mr. Breivik when he was a member of Norway’s conservative Progress Party in the early 2000s. “He’s one of the crowd, if you know what I mean. You forget him.”

Yet it was about a decade ago that Mr. Breivik started to change. Once a schoolboy who was fond of hip-hop and had a Muslim best friend, in his 20s he began to view the immigrants who flowed freely into Norway and elsewhere in Europe as enemies, and those who sought to accommodate them as traitors, worthy only of execution.

“Around year 2000 I realized that the democratic struggle against the Islamization of Europe, European multiculturalism, was lost,” he wrote in a manifesto that he published on the Web shortly before the attacks. “I decided to explore alternative forms of opposition. Protesting is saying that you disagree. Resistance is saying you will put a stop to this. I decided I wanted to join the resistance movement.”

With the 1,500-page manifesto, which he said took three years to complete, Mr. Breivik endeavored to find common cause with xenophobic right-wing groups around the world, particularly in the United States. He quoted extensively from the anti-Islam writings of American bloggers, and cut and pasted a whole section of the manifesto written by Theodore J. Kaczynski, known as the Unabomber, into his own, replacing “leftism” with “multiculturalism” as the object of aspersion.

“He has an apocalyptic view,” said Magnus Ranstorp, research director of the Center for Asymmetric Threat and Terrorism Studies at the Swedish National Defense College. “He thinks it will take 70 to 80 years to reverse the ‘Arabization’ of Europe. He sees himself as a part of history.”

Early in life, Mr. Breivik, far from being a radical, appeared to be on a track to join Norway’s political establishment. He grew up in Skoyen, a middle-class district of western Oslo. His father, a civil servant, and mother, a nurse, divorced when he was 1. Beyond that, his childhood seems to have been uneventful; Mr. Breivik said in his manifesto that it was happy.

He attended the elite high school where the country’s current king, Harald V, and his son once studied. Former classmates remembered him as quiet but intelligent, with a small rebellious streak: he was a prolific graffiti artist.

Toward the end of high school, he joined the youth wing of the Progress Party, drawn to its anti-immigrant platform and market capitalist bent. But those who knew him from those days said that he failed to leave much of a mark.

He began to struggle with life, those who knew him said. He became estranged from his father, who moved to France. Then his sister, Elisabeth, on whom he seemed to rely in his father’s absence, moved to the United States and married an American.

“Elisabeth was his only rock in life,” said a former childhood friend, who would not give his name for fear of reprisals because he is not an ethnic Norwegian. “When Elisabeth left, it really affected him. I think that’s when Anders began to spiral.”

It was a time when, according to his manifesto, his political views began to transmute. He began to perceive what he said was the hostility of Muslim youth. He latched on to reports of attacks against ethnic Norwegian men and rapes of ethnic Norwegian women by immigrant gangs.