The raid on Yokohama

At the end of May 1945 American B-29 bombers dealt the two heaviest blows of the entire campaign against the Japanese capital and its port. On the night of 23/24 May more than 500 Superfortresses burned out the southern districts of Tokyo; two nights later they burned the city centre, including the government district and part of the Imperial Palace; and on 29 May, in broad daylight, more than 450 bombers with a fighter escort reduced the centre of Yokohama to ashes.

Many war chronologies record under 23 May a “heavy bombing of Yokohama, an important port and naval base”. In fact the great raid on Yokohama took place on 29 May, whereas on the night of 23/24 May – as on the night of 25/26 May – the B-29s’ target was Tokyo, as confirmed by the official history of the US Army Air Forces (Craven and Cate) and by Japanese police data. Yokohama, moreover, was above all a great commercial port and industrial centre; the main naval base on Tokyo Bay was neighbouring Yokosuka.

The incendiary offensive returns to Tokyo

Since the night of 9/10 March, General Curtis LeMay’s XXI Bomber Command had known that low-level night raids with incendiary bombs could destroy Japanese cities built largely of wood. Through April and early May, however, some of the B-29s had to support the fighting on Okinawa by bombing the kamikaze airfields on Kyushu. Even so, in mid-April the Superfortresses burned out northern Tokyo, and on the night of 15/16 April Kawasaki and the northern outskirts of Yokohama as well.

In mid-May, when LeMay regained his freedom of action, a new and even more powerful wave of raids on the largest cities began. Nagoya was struck twice first – on 14 May and on the night of 16/17 May. By then the command had five bomb wings, based on Saipan, Tinian and Guam – according to American figures, some thousand B-29s.

The night of 23/24 May

On the evening of 23 May, 562 B-29s took off from the Marianas – the largest number of Superfortresses yet dispatched on a single raid. According to Craven and Cate, some 520 aircraft reached the target. They dropped incendiaries on the districts on the western shore of Tokyo Bay, south of the centre, where housing was interspersed with industrial plants. The fires consumed some 14 km² of the city. According to Tokyo police figures, some 760 people were killed – far fewer than in March, because many districts had already been partly evacuated, and after the March experience the inhabitants fled the flames more quickly. The Americans lost 17 bombers, and 69 were damaged.

The night of 25/26 May and the Imperial Palace

Two nights later, on 25 May, some 500 B-29s (464 over the target, according to Craven and Cate) struck central Tokyo – the area around Tokyo Station, the office districts, the ministries and the extensive residential districts of Yamanote. Some 44 km² of the city burned. The fire also spread to the Imperial Palace: the main palace building, erected in the Meiji era, burned down, even though the crews had orders not to aim at the complex, since Washington did not want to endanger the life of Emperor Hirohito. According to police figures, some 3,300 people were killed and some 166,000 buildings destroyed.

This time the Japanese defences proved effective – they shot down or destroyed 26 B-29s, the most on a single raid in the entire campaign, and damaged some 100 more. The same night several dozen Allied airmen, prisoners left behind in a military prison, died in burning Tokyo – some 50–60 people according to American studies; their deaths became the subject of war crimes investigations after the war.

After these two nights, by American calculations, roughly half (50.8 per cent) of Tokyo’s built-up area had been destroyed. The capital was struck off the list of targets for incendiary raids.

29 May – Yokohama

The last great raid of May was the attack on Yokohama. On the morning of 29 May, 517 B-29s were sent against the city, escorted by 101 P-51 Mustang fighters from Iwo Jima – the capture of the island now made it possible to cover the bombers on daylight raids over the main island of Japan. It was a daylight raid. According to Craven and Cate, 454 bombers got through to the city; in little more than an hour they dropped – according to Japanese researchers – some 2,500 tons of incendiaries on the city centre, the port and densely built-up residential districts.

Some 150 Japanese fighters intercepted the bombers, and a fierce air battle was fought over the city. The Americans lost between five and seven B-29s, according to various tallies, and some 175 were damaged; the P-51 pilots claimed 26 confirmed kills for the loss of three of their own aircraft.

The fires destroyed some 18 km² of the city. According to Japanese studies, more than a third of the buildings in the central, waterfront part of the city burned, and the whole city centre, except the Yamate district and the area around Yamashita Park, was turned into a burnt-out wasteland. American post-war estimates state that Yokohama lost some 40 per cent of its built-up area as a result of all the raids. The number of victims is disputed: American literature usually gives “more than a thousand” dead, Japanese studies from about 3,600 to 7,000–8,000, and some as many as 10,000. Many victims died around Koganechō Station, where the fire reached passengers on trains halted by the air-raid alarm.

Yokohama in the war

Yokohama had known bombs before. On 18 April 1942 it was one of the targets of the Doolittle Raid, the first American air raid on Japan. The port, through which a large share of Japan’s trade passed, was also an important supply hub, and the shipyards, chemical works and engineering plants on the waterfront worked for the military. Japanese researchers who analysed American documents after the war point out that the raid of 29 May was aimed primarily at densely populated residential districts rather than at the industrial plants on the bay.

Place in the war

The May raids on Tokyo and Yokohama completed the first stage of the incendiary offensive against Japan’s largest cities. According to the official history of the US Army Air Forces, some 240 km² of built-up area burned in May 1945, or roughly one-seventh of the country’s urban area. After these raids the Japanese Home Minister, Iwao Yamazaki, concluded that civil defence was futile. In June LeMay completed the destruction of Osaka and Kobe, after which the bombers moved on to dozens of medium-sized and small towns. Despite the unprecedented destruction and the civilian casualties, the Japanese leadership still rejected any thought of surrender.