Operation Bombing of Sendai

The 'Bombing of Sendai' was part of the strategic bombing campaign waged by the US 20th Army Air Force against the civilian population and military targets of the Japanese home islands in the closing stages of World War II (10 July 1945).

At the time of World War II, Sendai was the largest population and commercial centre of the Tohoku region of northern Honshu island, but lacked specific targets of strategic military significance. The Tohoku main line railway connecting Tokyo and Aomori also ran through the city.

Sendai’s first experience of Sendai with bombing came on 10 March 1945, when three Boeing B-29 Superfortress four-engined heavy bombers, which were part of a force slated to attack Tokyo, dropped their bomb loads on Mt Zao for unknown reasons, killing 34 civilians, and an additional two B-29 bombers attacked Sendai’s airfield, causing minor damage.

On 25 May, a B-29 photo-reconnaissance aeroplane overflew Sendai at an altitude of 8,000 ft (2440 m), providing data for the compilation of a detailed map of Sendai’s downtown area. On 10 July, another B-29 made an overflight of Sendai, this time dropping propaganda leaflets warning the residents of the city of its imminent destruction.

On 9 July, 131 B-29 bombers of Brigadier General LaVerne G. Saunders’s 58th Bombardment Wing took off from a newly completed airfield on Tinian island in the recently captured Mariana islands group. Several aircraft had to turn back as a result of mechanical problems, and 123 aircraft arrived over the target at an altitude of 10,000 ft (3050 m) at just after 00.00 in the early morning of 10 July. The bombers divided into 25 groups, each comprising between two and five aircraft, to carpet bomb the densely packed residential centre of the city with 10,961 incendiary bombs. The result was a firestorm which destroyed most of the city’s historic centre: a 1.93-sq mile (5-km˛) part of the city centre was destroyed, with 11,933 residences (about 23% of the city) destroyed by fire. Also lost in the bombing were a number of cultural treasures, include the structures of Sendai Castle and the Zuihoden mausoleum of the celebrated early 17th century regional ruler Date Masamune, founder of Sendai. On the other hand, the large Sendai Arsenal, and the buildings of the 2nd Division’s base remained untouched by the raid.

According to a survey report compiled by the defence division of Sendai’s administration during July, there were 987 dead, 50 missing, 260 seriously injured and 1,423 mildly injured. A year after the war, the US Army Air Forces’s Strategic Bombing Survey (Pacific War) reported that 21.9% of the city had been destroyed.

During the raid, the only US loss was one B-29 destroyed in a crash on the runway at Tinian, although its crew escaped without injury.

Sendai experienced a number of later air raids, though these were on a smaller scale. On 12 July, a single B-29 dropped 36 incendiary bombs on a Sendai suburb. On 13 July, 25 July, 9 August and 10 August, the city and its airfield were bombed and strafed by US Navy carrierborne aircraft.