[4] Gabrielsen was generally positive towards Finland, in a period when many Norwegian officials viewed the young country's national ambitions with suspicion.
In 1932 Gabrielsen even went so far as to suggest a strict regulation of Finnish priests' access to use churches in the Norwegian border areas.
[5] During the same year Gabrielsen was part of a group of officials that intervened after slate workers in Alta Municipality broke out in demonstrations and elected a company board dominated by communists.
However, after the sudden death of the County Governor of Troms a few days later he relocated to Tromsø and assumed the entire civilian administration for all of Northern Norway.
[8] Gabrielsen's and Fleischer's governance of Northern Norway had been highly popular with the local population, who felt that their views were finally being heard by those in control.
Due to this popularity of the improvised administration what was viewed as essentially as a switch back to central rule was not well received by the North Norwegian population, who wanted a voice in the government.
Gabrielsen felt that it would not be safe for the King and cabinet ministers to stay in the city of Tromsø, instead organizing housing for them in the surrounding areas.
King Haakon VII and Crown Prince Olav were relocated to the village of Øverbygd in the Målselvdalen valley, taking the prime minister, Johan Nygaardsvold with them.
Nygaardsvold brought along Minister of Social Affairs Sverre Støstad in order to maintain contact with his cabinet and avoid becoming isolated.
[14] When the Norwegian government evacuated to the United Kingdom in June 1940 they had given Gabrielsen the task of administrating the as yet unoccupied parts of Northern Norway.
The arrangement was supposed to last until the Germans could deploy forces to Eastern Finnmark, and was not cleared with the exiled Norwegian government, being secret for anyone but Gabrielsen.
As part of Ruge's plan Gabrielsen and Lindbäck-Larsen had placed Norwegian liaison officers on strategic points from Saltdalen in the south to Kirkenes in the north-east.
[15][18] The hope had been that a new Norwegian volunteer army would be allowed by the Germans to remain on border guard duties in Finnmark for the duration of the conflict.
These guard posts were set up on the secret orders of the German officer in charge of Eastern Finnmark, SS-Obersturmführer Willy Laqua, in accordance with the capitulation agreement.
The forestry work allowed easy access to food hidden in the woods by sympathizers, and messages could be smuggled in and out with little difficulty, making the Forest Gang the most popular assignment at Grini.
[23] Amongst the issues Gabrielsen discussed with fellow Grini inmates was the post-war reconstruction of Finnmark, most of the county having been laid waste during the German retreat in Northern Norway in 1944—1945.