The German army had experience in fighting airplanes with anti-aircraft artillery from the period of the First World War. However, in the 1920s and 1930s, the development of anti-aircraft artillery, although it did take place, was not treated as a priority in Germany. It should be added, however, that in the 1930s, the very successful 88 Flak 18 cannons (along with subsequent versions), as well as the 37 mm Flak 18 cannon and 20 mm Flak 30 and Flak 38 cannons were introduced into service. These weapons were responsible for providing air defense primarily to their own land units, although it was assumed that the German Luftwaffe would dominate the air over the battlefield, and that the land forces would face a limited threat from enemy aviation. Such assumptions influenced, among other things, the fact that the German infantry division in 1939 had only 12 20 mm anti-aircraft guns. However, with the growing air superiority of the Soviet, and especially the Allied, air forces, the German army began to intensively develop its own anti-aircraft defense (especially from 1943). In addition, there was also the need to provide air defense to German cities and factories that were forced to deal with Allied strategic air raids. The latter threat increased the production of such cannons 10.5 cm FlaK 38/39 how or 12.8 cm FlaK 40 .