During the Pacific War, Allied forces conducted air raids on Japan from 1942 to 1945, causing extensive destruction to the country's cities and killing between 241,000 and 900,000 people. During the first years of the Pacific War these attacks were limited to the Doolittle Raid in April 1942 and small-scale raids on Japanese military positions in the Kuril Islands from mid-1943. Strategic bombing raids began in June 1944 and continued with increasing intensity until the end of the war in August 1945. Allied naval and land-based tactical air units also attacked Japan during 1945.
The United States Army Air Forces (USAAF) campaign against Japan began in earnest in mid-1944 and intensified during the final months of the war. While plans for attacks on the Japanese home islands had been prepared prior to the Pacific War, these could not begin until the long-range Boeing B-29 Superfortress bomber was ready for combat and in production at scale. From June 1944 until January 1945, B-29s stationed in India and staged through bases in China made a series of nine raids on targets in western Japan, but this effort proved ineffective. The strategic bombing campaign was greatly expanded from November 1944, when airfields in the Mariana Islands became available as a result of the Mariana Islands Campaign. Initial attempts to target industrial facilities using high-altitude daylight "precision" bombing were ineffective in significantly degrading Japanese war economy, due to a mix of poor weather conditions, Japanese air defenses, and the jet stream impeding accuracy.