Such openness could now be at an end after Anders Behring Breivik's devastating car bomb attack on the prime minister's offices and the slaying of young activists from the ruling Labour party trapped on an island.
The attacks, in which at least 93 people were killed, will also affect Norway's debate on immigration but are unlikely to close the shutters of one of Europe's most open societies.
"We will have a society based on less trust ... we will be a bit more anxious than before," said Thomas Hylland Eriksen, a social anthropologist from the University of Oslo.
Stoltenberg said on Sunday that Norway would "keep going" but that there would be a definite break between the country before and after the attacks.
"But I am quite sure that you will also recognize Norway afterwards -- it will be an open Norway, a democratic Norway and a Norway where we take care of each other," Stoltenberg said.
Breivik, who admitted to the shooting spree and bomb blast, has said through his lawyer that his actions aimed to "change Norwegian society" which he saw as being undermined by multi-culturalism.
"BESLAN-LIKE CRUELTY"
Analysts say the scale and brutality of the attacks shattered Norway's self-image as a peaceful nation focused on mediation efforts across the globe and the Nobel Peace Prize.
"The lesson here is that fanatics do and will continue to exist -- and that Norway is not immune," said political science professor Janne Haaland Matlary.
Security officials have refused to confirm they were aware of Breivik as a potential threat, although publicly there is little to indicate he was on any watchlist. His only criminal record appears to be a traffic conviction 10 years ago. Other questions over the police response to the massacre remain unanswered after officers confirmed an hour elapsed between being alerted and stopping the massacre.
Erik Berga, police operations chief in Buskerud County, said an inadequate boat and a decision to await a special armed unit from Oslo, 30 miles (45km) away, hampered the response. "When so many people and equipment were put into it, the boat started to take on water, so that the motor stopped," she said.
On Sunday it emerged that a police officer had been guarding the island but it is thought he was killed by the gunman.
Breivik's father, Jens, said he had learned of his son's involvement online. "I was reading the online newspapers and suddenly I saw his name and picture on the net," he told the VG tabloid.
"It was a shock to learn about it. I have not recovered yet," he said. Jens, who is in his 70s, lives in France and has had no contact with his son since 1995, according to Reuters.
The Norway attacks have raised concerns copycat operations may take place in Europe. British Muslim leaders announced on Sunday increased security at mosques. Mohammed Shafiq, the leader of Ramadhan Foundation, one of Britain's largest Muslim groups, says mosques were being extra vigilant.
Shafiq said he was also discussing the need to take extra precautions with other European Muslim leaders, adding that he has spoken to the police about extra protection.
Concerns the UK remains vulnerable to such an attack were aired by the foreign secretary, William Hague, who warned that Britain's security forces may not be able to stop a Norway-style terror attack.
However, security experts said the events in Norway last Friday would refocus how far-right groups are dealt with.
Dr John Bew, director of the International Centre for the Study of Radicalisation and Political Violence at King's College London, admitted there had been a lack of focus on far-right extremism, with research into Islamism often taking precedence. "We have looked at lone wolves in relation to Islamism but I think we haven't taken far-right extremism seriously enough."
James Brandon, research head at London's Quilliam thinktank, said: "The horrific events in Norway are a reminder that white far-right extremism is also a major and possibly growing threat."
Norway is still struggling to come to terms with the attacks, which came within two hours of each other on Friday afternoon. Breivik was arrested after surrendering on the island, where he had shot and killed at least 86 young people at a summer camp run by the ruling Labour Party. Seven civil servants died after he detonated a massive car bomb in Oslo's government district 90 minutes earlier.
