The Waffen SS during 1940 French blitzkrieg (en Inglés) - Guglielmo De Marchi

At dawn on 10 May 1940, the Wehrmacht launched Fall Gelb, the offensive that would lead to the collapse of France and the humiliation of the British expeditionary force in just a few weeks. 

In what would become universally known as Blitzkrieg, it was not only the Wehrmacht's panzers and divisions that played a leading role. Alongside them, or more often in their immediate rear and then gradually inserted more and more into the thick of the fighting, the young divisions of the Waffen-SS also advanced. For the first time, the SS was deployed on an army corps scale in a military campaign of primary importance. 

The 1940 French Campaign was therefore a crucial test and a turning point for the Waffen-SS, an experience that marked their transition from a politicised police force to a parallel army competing with the Wehrmacht (which was destined to become the spearhead of the German armed forces).