Nordic countries surrendered so easily during World War II.

Norway: Norway was invaded by the Allied Forces and Axis Powers in World War II. Norway is close to the British mainland, and shore-based aircraft can directly harm the British offshore. Norway's unique fjord terrain has also become a natural harbor for the navy. Finally, Norway is located at the mouth of Jutland Strait, which is an important throat of German iron ore transportation line. Therefore, Norway has become a strategic place for the Allies and Axis countries to compete for. From 1938 to 1940, Germany launched the Weseth exercise.

Denmark: After the Weseth exercise began, the King of Denmark announced his surrender and Denmark became a puppet country of Germany. Denmark was also the least controlled by Germany among all the German puppet countries during World War II, and Germany gave Denmark full freedom.

Sweden: Sweden remained neutral in World War II, but actually maintained a friendly neutral policy towards the Axis countries. Despite British pressure, Sweden still exports a lot of iron ore to Germany and maintains close economic and trade exchanges with Germany. In the Barbarossa Plan, Sweden gave Germany the right of military passage, so Germany could cross Sweden from Norway and directly enter Finland to fight against the Soviet Union.

Finland: Finland was invaded by the Soviet Union in 1939, which is known as the Sufen War or the Winter Campaign. The aftermath of the purge was completely exposed in the Sufen War, and the Soviet army struggled to defeat Finland with a population of only 3 million. Finland joined the Axis camp in the Barbarossa Plan and declared war on the Soviet Union together.