On the 9th May, 1942, the american War Department issued an order to the Commanding General, Ground Forces, starting with:

”1. It is desired that you take the necessary steps to organize at the earliest practicable date a battalion of Norwegian nationals to serve as part of the US Army.

2. This unit will be organized as an Infantry Battalion. (..)”

All men who were transferred, or volunteered, to the 99th battalion, had to know how to speak norwegian, and many originated from the ”norwegian” areas in Minnesota. Only a very few had actually ever been to Norway, but as many as 950 men of Norwegian heritage started their basic education at Camp Ripley, Minnesota.

(The original purpose of 99th, was to participate in ”Operation Plough” – the concept of advanced sabotage actions in Norway, and men from this unit were the only americans ever to operate on Norwegian soil during WW 2. That particular operation was ”Operation Rype” in the Tröndelag area. The "Rype" group consisted of 15 men, and they were transported in two groups. The first group, however, jumped out over Swedish territory, and got interned for a period.
This operation, main target: the railway, took place during the autumn of 1944, and consisted of a group of saboteurs led by Major William Colby. They stayed in the border areas between Norway and Sweden until the liberation of Norway.
The ”Rype” group is also known for an incident which took place on the 2nd May, 1945, when they caught a German patrol consisting of 1 Leutnant with 4 men. The Germans were executed a few hours later, after having been forced to dig their own graves.) 

The 99th Battalion was to consist of a mixture of infantry,- parachute,- and mountaineer specialists, and their insignia was a shield with a Viking ship, in the Norwegian national colors red, white and blue.
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In 1944, 99th was sent to the UK, and were to participate in the invasion of France. Shortly, these are the Battles that they were engaged in: The Normandy Campaign, The North France Campaign, the Battles at Würzeln / Aachen, and the Battle of the Bulge. About 300 men were killed or heavily injured, and these were replaced by new ”norwegians”.

In may 1945, the 99th finally arrived in Norway, and needless to say, this must have been a very special moment for the 2nd and 3rd generation Norwegians. They stayed in the Oslo – Drammen area, and their task was guard duties during the repatriation of the 375 000 Germans.
In October, they were sent to the US, and arrived in Boston late that month. However, more than 50 men came home with a new Norwegian wife. The Battalion was disbanded shortly after.

In Norway: soldiers of the 99th sending liberated 
russian POWs back to soviet

The 99th Battalion (separate) teoretically belonged to the 474th Infantry Regiment, first being sub coordinated to 2nd Armored Division, later 30th Infantry Division, XIX corps. (XVIII Airborne corps from January 1945) 
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