Although simple incendiary bombs have been used to destroy buildings since the start of gunpowder warfare, World War I saw the first use of strategic bombing from the air to damage the morale and economy of the enemy, such as the German Zeppelin air raids conducted on London during the Great War. The Chinese wartime capital of Chongqing was firebombed by the Imperial Japanese starting in early 1939. London, Coventry, and many other British cities were firebombed during the Blitz by Germany. Most large German cities were extensively firebombed starting in 1942, and almost all large Japanese cities were firebombed during the last six months of World War II.