 Complete the following phrase:  During the Franco-Prussian War, the Prussians and later the Germans made their own version of the battle of annihilation by destroying entire armies relatively fast by means of rapid troop movement and rapid encirclement of the enemy. Those tactics came into fruition during the decisive battles of Metz and Sedan in which two main French armies were completely annihilated at the same time and relatively quickly, rendering France almost completely defenseless against the German invasion. Those tactics later served to inspire the blitzkrieg during World War II, with highly-mobile formations executing a battle of annihilation by charging straight into the enemys weak point and attempt to encircle and destroy separate enemy pockets. The tactics became spectacularly successful during the German invasions of Poland, France and the Soviet Union until they themselves became annihilated by the Soviets in battles such as Stalingrad, 