The Luftwaffe (German pronunciation: [ˈlʊftvafə] (listen)) was the aerial warfare branch of the Wehrmacht during World War II. Germany's military air arms during World War I, the Luftstreitkräfte of the Imperial Army and the Marine-Fliegerabteilung of the Imperial Navy, had been disbanded in May 1920 as a result of the terms of the Treaty of Versailles which stated that Germany was forbidden to have any air force.
During the interwar period, German pilots were trained secretly in violation of the treaty at Lipetsk Air Base in the Soviet Union. With the rise of the Nazi Party and the repudiation of the Versailles Treaty, the Luftwaffe's existence was publicly acknowledged on 26 February 1935, just over two weeks before open defiance of the Versailles Treaty through German re-armament and conscription would be announced on 16 March. The Condor Legion, a Luftwaffe detachment sent to aid Nationalist forces in the Spanish Civil War, provided the force with a valuable testing ground for new tactics and aircraft. Partially as a result of this combat experience, the Luftwaffe had become one of the most sophisticated, technologically advanced, and battle-experienced air forces in the world when World War II broke out in 1939. By the summer of 1939, the Luftwaffe had twenty-eight Geschwader (wings). The Luftwaffe also operated Fallschirmjäger paratrooper units.