Norway was invaded and occupied by Nazi Germany in April 1940, and remained under occupation for five years until the end of the war in Europe. During the early period of the war, Norway also played an important role in the Allied campaign to prevent the Germans from obtaining an atomic bomb.
Operation Weserübung
On 9th April 1940, Germany invaded Denmark and Norway in a surprise attack called Operation Weserübung. The attack, which was ordered by Adolf Hitler, was designed to secure the Norwegian coast to provide bases to German warships and submarines and secure access to the important iron ore mines in northern Sweden, via the port of Narvik.
Norways defence of its country
While the Norwegian armed forces were understrength and ill-equipped to resist the German invasion, they managed to hold out for several days. The Norwegian government resisted the German invaders by moving the Norwegian gold bullion reserve from Oslo to the interior of the country. The gold was ultimately shipped to Canada. The government managed to escape to Britain from where it continued the fight against the German occupation.
German victory in Norway
Despite heroic resistance, the German forces eventually overwhelmed the Norwegian defence. On the 9th June, the last Norwegian and British troops withdrew from northern Norway. The Norwegian king and government, and many troops were evacuated to the United Kingdom.
Norway in exile
The exiled government of Norway and large numbers of Norwegian volunteers in the Norwegian armed forces continued to fight the Germans from abroad with the Allies for the remainder of the war. The Norwegian Merchant Fleet joined the Allies in the Battle of the Atlantic. Some 200 Norwegian ships were lost during the war, and around 3,000 Norwegian merchant seamen died.
From the summer of 1940, the Soviet Union supplied arms to the communists within the Norwegian resistance movement, and to a lesser degree, also to their main non-communist competitors. The United Kingdom also provided supplies but was constrained by its own desperate military situation in 1940 and 1941. Britain gave increasing quantities of supplies during the course of the war, both to the Communist and non-communist resistance movements.
Despite the dangers, the Norwegian resistance movement launched over 1,500 sabotage missions against German targets - more acts of resistance per capita than any other country in German occupied Europe.
Following the Allied victory in Europe in May 1945, the German occupying forces in Norway surrendered to the Allies. The next day, the exiled government returned to Norway and took over the administration of the country.