The country closed a tragic chapter on Friday when an Oslo court sentenced Breivik to Norway's maximum sentence -- 21 years in prison, to be extended if he is still considered a threat to society -- for the July 2011 bombing and shooting frenzy that left 77 people dead.
"Never has the word relief been uttered as often in a courtroom as after the verdict yesterday," the Aftenposten newspaper said in an editorial on Saturday.
That feeling was shared by the survivors of the Utøya island shooting spree, where the 33-year-old right-wing extremist spent more than an hour gunning down 69 people, mostly teenagers, after he killed eight people in a van bombing outside the government offices in Oslo.
"This crap is finally over. Life can start now," survivor Ingrid Nymoen posted on Twitter.
The sense of relief was bolstered by the fact that the verdict was likely to be definitive, with both the prosecution and defence saying they did not plan to appeal.
Norway can now put the trial -- and the cathartic process it enabled -- behind it and address the shortcomings Breivik's attacks brought to light in its traditionally liberal society viewed by some critics as naive.
An independent commission set up by Prime Minister Jens Stoltenberg recently issued a scathing report on the authorities' handling of the attacks, concluding that the Oslo bombing could have been prevented.
Breivik's shooting spree, Europe's deadliest rampage by a lone gunman in peacetime, could also have been stopped sooner, it said.
The report, published on August 13th, prompted the national police commissioner to resign.
The commission condemned apathy it said rose to the highest levels of the state, noting that it failed to implement a 2004 decision to partially block off a government block from traffic.
That made it possible for Breivik to park a van loaded with almost a tonne of explosives at the foot of the 17-storey tower housing the prime minister's offices.
The day after the report was published, tabloid Verdens Gang (VG), Norway's most widely-read paper, called on Stoltenberg to assume responsibility and resign.
While a majority of Norwegians think Stoltenberg should stay on, the newspaper's call and the echoes since have weakened the prime minister, just a year ahead of legislative elections which the government is not certain of winning.
Stoltenberg will, at his own request, address parliament on Tuesday about the report, calling in legislators during their summer break for an extraordinary session.
The meeting is aimed at learning lessons from the commission's criticism, primarily regarding the police's bungled response to the attacks which probably cost lives.
The only police helicopter was out of action because its crew were on holiday, and a SWAT team took more than an hour to finally make it to the island, forced to use a pleasure boat after their inflatable almost sank.
The right-wing opposition has not ruled out the possibility of calling a motion of no-confidence against the government.
But such a move would be purely symbolic as the centre-left coalition government holds a majority in parliament.