The decisive influence on the shaping of the organization and tactics of the German infantry before the outbreak of World War II was, on the one hand, the experience of the previous World War, but also theoretical works created in the 1920s and 1930s, which often emphasized the need to perceive the German infantry as a tool waging an offensive war. This affected both the equipment and the organization of the German infantry division, which during the September campaign of 1939 consisted of 3 infantry regiments, each of which was divided into 3 infantry battalions, an artillery company and an anti-tank company. In addition, there were numerous support units, including: an artillery regiment with 4 artillery squadrons (including one heavy), an anti-tank battalion, a sapper battalion and a communications battalion. In total, the so-called infantry division In the first mobilization wave, there were approximately 17,700 people and had a significant artillery component, but also was abundantly equipped with machine guns. It also had modern and efficient - for those times - means of communication and command. In the course of the war, infantry divisions underwent transformation - in 1943 some of them were transformed into armored grenadier divisions. However, from 1943, the standard division of the "traditional" infantry consisted of approx. 12,500 men (and not approx. 17,700 as in 1939), and its artillery component - especially heavy artillery - was also reduced in it, while its anti-tank defense was significantly improved. It is assumed that during the entire Second World War, about 350 infantry divisions served in the Wehrmacht.
Operation "Marita" is the German code name for the operation carried out in the area of Balkan in the period from 6 to 29 April 1941. The main opponents of the Axis forces (Germany, Italy, Bulgaria) in this conflict were the Yugoslav and Greek troops supported by British, Australian and New Zealand units. It is worth adding that the plan initially assumed actions only against Greece, but due to the change of government in Yugoslavia to anti-German, the plan was hastily modernized and also aimed at this country. The main burden of campaigning on the side of the Axis powers rested with the German army, which operated against both Yugoslavia and Greece. As in the course of the campaign in Poland (1939) and France (1940), the German side applied the Blitzkrieg doctrine, concentrating significant air and armored forces to operate. As a result of the very clear superiority of the Axis forces on land and in the air, Yugoslavia capitulated on April 17, 1941, and Greece fought until April 23 of the same year. As a result of the operation, the German army lost only about 2,000 killed and about 4,200 wounded. On the other hand, about 370,000 Yugoslav soldiers and about 220,000 Greek soldiers were taken prisoner! However, it should be remembered that the campaign in the Balkans delayed the German attack on the USSR, which, according to some researchers of the topic, was one of the indirect reasons for the German defeat in the Soviet Union. It is also worth remembering that the occupation of Yugoslavia and Greece involved about 250,000 German, Italian and Bulgarian soldiers
Despite their defeat in World War I, the German officer corps in the interwar period still saw the main means of victory in a future war in an offensive operation. Thus, he drew a different experience from the Great War than his French counterpart. Based on the experience of 1914-1918, including the infiltration tactics used by the Stosstruppen troops, but also noticing the intense development of aviation and armored weapons, part of the German officer corps (e.g. Gen. Heinz Guderian) developed theoretical assumptions of the so-called lightning war (German: Blitzkrieg), that is, striving to knock down the enemy with one decisive offensive operation carried out in the shortest possible time and with the maximum intensity of forces and resources. The German officer corps was also trained according to this offensive doctrine of war in the 1930s and during the world war. It is also worth adding that German officers of almost all levels in the course of World War II used the principle of the so-called command by task (Ger. Auftragstaktik), that is, they outlined to their subordinates the task to be achieved and the forces at their disposal, while the execution of the task was entirely up to them. Such a model of command, based on very well and uniformly trained officers, led to the fact that the German army was highly flexible in action and was able to react faster to various levels than its opponents (e.g. the French army during the campaign of 1940 or Soviet army of 1941). This system proved successful (especially at lower levels) throughout World War II. It is also worth adding that many outstanding commanders served in the German officer corps from the Second World War, including: Erich von Manstein, Heinz Guderian, Erwin Rommel and Walter Model.