His brother, then army captain Halvor Løken, bid him farewell at the docks with the words "It's a comfort to know that ill weeds never wither" (Norwegian: "Det er jo en trøst å vite at ukrutt ikke forgår så lett"), in reference to the unhealthy and dangerous conditions then to be found in the Congo Free State.

[8][Note 2] Løken's group of officers first underwent a three-month colonial training course in Brussels, Belgium, before being shipped to the Congo.

[12] He remained in Force Publique service after Leopold II of Belgium gave up his personal control of the territory in 1908 and transferred it to the Belgian state.

In 1918 he attended a hand grenade course, in 1919 the Norwegian infantry shooting school, in 1921 a machine gun course and in 1928 a tactical command course.

[28] Following the invasion of Norway and the German attack on Narvik on 9 April 1940, by 3rd Mountain Division troops led by Generaloberst Eduard Dietl, Løken was responsible for carrying out the Norwegian mobilization in Troms.

In the evening of 8 April, Colonel Løken had been ordered to send his infantry battalion and a motorized artillery battery to Narvik to defend the town, but the transfer of forces was pre-empted by the German landing.

[31] In maintaining a defensive posture with almost his entire force during the mobilization stage, Løken came into disagreement with the top leadership of the 6th Division, which wanted a swift counter-attack against the Germans as soon as possible.

[32] Despite not mounting an immediate counter-attack, Løken did move troops forward to blocking positions further south than planned, as he saw it as important to stop the German advance in Gratangen Municipality.

[33] Colonel Løken's more cautious approach to warfare lead to a deterioration of his relationship with the more offensive division commander, Carl Gustav Fleischer.

[35][36] During this time, Løken first had his headquarters at Kroken in the Salangsdalen valley in Troms county, before it moved forward to Fossbakken in Lavangen Municipality.

While the main attack failed, the flank march of the 1st Battalion, 12th Infantry Regiment was counter-attacked by the Germans, the Norwegians suffering heavy losses and being routed.

[39] After the failed initial offensive, Løken severely criticized the commander of the 1st Battalion, 12th Infantry Regiment, Major Nils Christoffer Bøckman, for having bypassed Løken's brigade command in order to receive permission to advance directly from the 6th Division, exposing his unit to counter-attack.

While the 6th Brigade was to follow a generally mountainous advance route against the Germans, the 7th was to attack along the coast in cooperation with French expeditionary forces.

[42] The 6th Brigade carried out a hard-fought mountain campaign over the coming weeks, pushing the Germans southwards along the Swedish border.

Failure on the part of Løken to act on this information and seize the plateau allowed the Germans to occupy and fortify the feature on 7 May 1940, requiring heavy fighting a week later before they were dislodged.

[45][46][47] The appointment was formally confirmed by royal resolution on 31 May 1940, at a meeting of the King and Cabinet at Storsteinnes in Balsfjord Municipality, Troms county.

[54] Before releasing the Norwegian officers from captivity, the Germans demanded that each gave their word of honour not to participate in further resistance.

[55] Following the Norwegian capitulation, Colonel Løken worked on maintaining order and calm in Northern Norway in the transition phase to German occupation.

While interned at Oflag XXI-C, Løken shared a room with Colonel Johannes Schiøtz, with whom he had attended the Norwegian Military Academy close to four decades earlier.

The Norwegian prisoners of war remained interned at Oflag III-A until their German guards abandoned the camp on 21 April 1945, with Soviet forces arriving the next day.

On 10 May 1945, two days after the end of the war in Europe, the Norwegian prisoners left Luckenwalde, reaching Norway in several groups in late May/early June 1945.

[62] On 1 August 1949 he formally retired from the Norwegian Armed Forces, yet continued working for several years under temporary contracts.