The Labour Party in Trondheim prioritised the work to establish a new newspaper, and at the annual meeting it created an extra member fee for the purpose.
During World War II and the German occupation of Norway the entire media environment in Trondheim changed.
In article and editorials there were clear stands in cases that were in conflict with the German interests, resulting in that the newspaper was stopped for shorter or longer periods.
The three other Trondheim newspapers barely mentioned the event with a small notice from central authorities: "Arbeider-Avisen has lately repeatedly published articles and messages that only has had the intention of giving an unwanted influence on the newspaper's readers, and by that evading civil obedience, at the same time it is damaging the work that Norwegian and German authorities are conducting in cooperation.
The newspaper's editor Harald Langhelle was in October 1942 arrested and executed as one of ten after a sabotage at Fosdalen Mines in Malm Municipality.
It was produced at Adresseavisen after press from the resistance, who wanted to avoid to much unfair competition because of the many newspapers that were stopped during the war.
But thanks to hard work from former employees and not least the labour unions, the newspaper could again start production, layout and printed at Adresseavisen, with Ole Øisang back as editor.
In 1964 the newspaper merged with Namdal Arbeiderblad in the company A/S Trønderpresse and some time later with Stjørdalens Blad to strengthen the economy, something that also happened.
Only once, in 1971, has the newspaper been close to the target issue number of 20,000, right before the 1972 Norwegian European Communities membership referendum.
Editor Eigil Gullvåg took a stand for Norwegian EEC membership, unlike most of the opinion in Central Norway and among the newspapers readers and the growth was changed to decline.
Norsk Arbeiderpresse (now A-Pressen) went into the ownership of Arbeider-Avisa in the late 1980s and declared the newspaper a priority area, but neither this put an end to the rumours of an imminent death.
After 45 years in Folkets Hus in Midtbyen Arbeider-Avisa moved the offices and press to a new building in Lade in 1990 under leadership of editor Bjørn Stuevold.
In Folkets Hus in the city centre the offices had grown so much it had been in four floors, connected through labyrinths of corridors.