For the Netherlands, the Second World War began on 10 May 1940, when Germany launched a surprise invasion in the early morning. To conceal the attack, German aircraft first flew over the North Sea and then turned back, dropping paratroopers and deploying soldiers using aircraft near important bridges and airfields. Fierce fighting took place in several locations. Capturing the queen and the government in The Hague was an important objective in order to break Dutch resistance. However, they managed to escape in time to England.
On 14 May 1940, Rotterdam was heavily bombed, killing nearly a thousand people and destroying the city centre. The threat that other cities might suffer the same fate forced the Netherlands to surrender. From that moment on, the German occupation of the Netherlands began.
Initially, England was also planned to be attacked across the sea by the German army, but the air battle was not won by the end of 1940, so this German plan was abandoned. This meant that the coast had to be heavily guarded day and night so that the Allies could not simply land. When the invasion of the Soviet Union stalled at the end of 1941, the Germans became increasingly fearful of this situation. They did not want to fight a war in both the east and the west. To prevent this, the Atlantic Wall was conceived: a strong defensive line of bunkers along the coast.