Japanese air raids on Calcutta

War chronologies record under 23 December 1942 that the Japanese air force began bombing Calcutta. The date needs shifting slightly: the first raid came on the night of 20–21 December, and 23 December was one of several that followed, repeated almost every night until Christmas. Calcutta – the largest city of British India and its capital until 1911, a port on the Hooghly and, since the fall of Burma, the main supply base for the Burma front – felt the war directly for the first time. The bombs did little damage, but they caused panic and a mass flight of the inhabitants that paralysed the life of the city for several weeks.

War at the gates of Bengal

Calcutta had been expecting an attack since the spring of 1942. In April a Japanese carrier force entered the Indian Ocean, and its cruisers and aircraft sank more than twenty merchant ships in the Bay of Bengal and bombed ports on India’s east coast. In May the British and Chinese were driven out of Burma, and the Burma campaign ended on the Indian frontier. From then on Calcutta lay within range of Japanese bombers flying from airfields in Burma. The mood in Bengal was also darkening for another reason: after the arrest of Gandhi and the leaders of the Indian National Congress in August 1942, the province, like other parts of India, was swept by demonstrations, strikes and sabotage, which the colonial authorities suppressed.

The city’s importance could hardly be overstated. Calcutta had more than two million inhabitants; it was a centre of the jute and engineering industries and the seat of the banks and trading houses of the whole of eastern India. Through its port and railway junction passed supplies for the troops defending the Burmese frontier and for the airfields in Assam, from which American transport aircraft flew cargo over the Himalayas to China, cut off from the world since the loss of the Burma Road. The Commander-in-Chief in India, General Archibald Wavell, was just then preparing the first, limited offensive in the Arakan, and Calcutta was its base.

During the monsoon the Japanese air force was largely inactive. When the rains stopped, the Japanese Army Air Force began attacking airfields in Assam and around Chittagong. According to post-war British studies, the raid on Calcutta, prepared by the 7th Air Brigade, was originally planned for 5 December but was postponed. Its targets were to be the port, where reconnaissance had spotted a large number of ships, and the industrial plants along the Hooghly.

The nights before Christmas

On the night of 20–21 December, according to British accounts, about eight twin-engined Mitsubishi Ki-21 bombers, known to the Allies as “Sally”, appeared over the city. The bombs fell scattered, among other places on the oil tanks at Budge Budge south of the city and on streets in the centre. The Japanese returned on the following nights, including 23 December, and on Christmas Eve about ten bombers dropped their loads on the city centre around Chowringhee and Dalhousie Square, where Europeans lived and worked. According to some sources, further smaller raids took place after Christmas, until 28 December. The bomb loads were small, because the aircraft were operating at the limit of their range, while darkness and anti-aircraft guns forced them to release from high altitude. Howrah Bridge, the most important crossing of the Hooghly, was left untouched.

Flight from the city

The material damage and the number of casualties in December 1942 were small compared with the raids on European cities; exact figures are lacking, because wartime censorship restricted press reporting. The psychological effect was far more serious. After the first raids crowds began to flee Calcutta. Estimates vary enormously: various sources speak of 350,000 people, and some Indian studies of as many as one and a half million, who left the city at least for a time. Those who fled were above all migrant workers from country villages: porters and dock labourers, workers from the factories along the Hooghly, servants and municipal sweepers. According to accounts from those weeks, rubbish piled up in the streets and the authorities feared epidemics. The port, through which passed supplies for the troops in Assam and on the Burmese frontier, was short of labour.

The city’s air defences in December 1942 were weak. Calcutta was protected by Hawker Hurricane fighters, unsuited to night fighting, and a handful of anti-aircraft guns. The Hurricanes scrambled at the alarm, but without airborne radar they seldom found the enemy; the only certain success, a bomber shot down on Christmas Eve, was widely publicised in the press. For years India had served the British air force as a backwater that received obsolete equipment, and only the war with Japan changed this.

Its place in the history of the war

The answer came in January 1943. A few Bristol Beaufighter night fighters with airborne radar were transferred to Calcutta from Egypt, and on 15 January they were formed into No. 176 Squadron RAF. The very next night one of its pilots, Sergeant Maurice Pring, shot down three Japanese bombers within a few minutes; they fell in full view of the inhabitants. After further losses the Japanese abandoned their night raids on the city. The raids returned in a different form on 5 December 1943, when aircraft of the Japanese Army and Navy air forces attacked the Kidderpore docks by day; according to various sources, between several hundred and about five hundred people were killed. Sporadic attacks continued into 1944, when the Japanese air force in Burma began to lose the struggle for air superiority.

The December raids were of secondary military importance. They interrupted neither the supply of the front nor the preparations for the first British offensive in the Arakan, which was just beginning. They did show, however, how fragile the rear of British India was. Disruption of the rice trade, the loss of imports from Burma, the policies of the colonial authorities and wartime priorities in supplying Calcutta led in 1943 to the Bengal famine, in which, by various estimates, between 2 and 3 million people died. The raids on Calcutta belong to its background rather than its causes, but that winter began a long period of fear, scarcity and distrust of the British authorities in Bengal.