* Actions of the German air force during the Spanish Civil War * Covers the bombing of Guernica and other events * Draws from previously undiscovered source material In 1936, civil war broke out in Spain, a violent prelude to World War II. Germany and the Soviet Union clashed there by proxy, with Hitler supporting Franco's Nationalists and Stalin aligning with the Republicans. The Third Reich sent the Condor Legion, a unit composed primarily of Luftwaffe forces, and the conflict became a proving ground for concepts like blitzkrieg, for officers like Adolf Galland and Werner Molders, and for aircraft like the Bf 109, He 111, and Ju 97. Chillingly, the war also saw the development of terror bombing.