Guard and patrol duty in the border areas brought the battalion near the brutality of war and served to harden the men of the unit.

After seeing the fighting and burning town in Petsamo the soldiers and officers of the Alta Battalion began to view war as a reality and not merely something found in the history books.

After the German invasion of Norway on 9 April 1940 the battalion was once more mobilized, the soldiers making their way to Alta by boats or reindeer sleds, then being transported to the front area by the Hurtigruten steamships SS Dronning Maud and Kong Haakon, and the cargo ship Senja.

[3] The unit spent the entire two-month campaign conducting offensive operations against general Eduard Dietl's entrenched troops.

In the mountainous inland areas of the front the Alta Battalion was continuously on the attack, suffering many casualties in the process of throwing back the crack German troops.

In addition Alta Battalion also formed smaller local forces in western Finnmark, including an air warning unit of fifteen men in Kårhamn.

Without the support of the RAF and the Royal Navy the Norwegian government lost all hope of prevailing against the Germans, and fled the country with the evacuating Allies.

After the conclusion of the campaign Eduard Dietl commented that at the time of the Norwegian capitulation his forces would have been able to hold out for only another 24 to 48 hours, after which they would have had to abandon the entire Narvik front and cross into Sweden.

As the still undefeated units of the 6th Division, amongst them the Alta Battalion, marched down from the snow-covered hills on 9 June 1940 many of the soldiers cried tears of bitterness and disappointment that victory had been snatched from them.

During the early hours of the 10th the soldiers of the battalion marched to Grovfjord, under intermittent air attacks, from where they embarked fishing boats for the journey back to Altagård.