The German invasion of Norway began on April 9, 1940, as part of Operation Weserübung, which aimed to secure strategic territories in Scandinavia. The Norwegian forces faced overwhelming odds against the technologically superior German military, which included tactical bombings and paratrooper landings that seized key locations swiftly. The Norwegian army, although initially taken by surprise, managed to muster a strong defense and even achieved some early successes. However, the situation deteriorated as German reinforcements arrived and new campaigns commenced, specifically targeting critical areas such as Narvik and Oslo.

By June 1940, a series of defeats left Norwegian forces unable to continue organized resistance. Allied support, which included British forces attempting to reinforce the Norwegian campaign, was ultimately ineffective due to the rapid German advance and logistical challenges. The last Norwegian forces organized to resist were faced with a stark choice: to continue fighting against overwhelming odds or to surrender. After a brief period of deliberation, Norway officially capitulated on June 10, marking the end of military resistance. This surrender was not just a military loss; it reflected the shifting tides of World War II with the Axis powers gaining strength in Northern Europe.

Post-surrender, Germany established an occupation regime in Norway that would last until 1945. The occupation had profound impacts on Norwegian society, politics, and the economy, fostering a legacy of resistance among the population. Despite the official military surrender, many Norwegians continued to resist through various means, including espionage and supporting the Allies through intelligence and logistics.