last year of peace Japanese vessels had only been able to carry 65% of her imports.19 Although the production of cargo ships was to be greatly increased during the war their numbers and tonnage were never sufficient to offset those being sunk and this was to remain a major constraint on Japanese strategy.20 The overall decline in available merchant vessels together with the ever increasing scale of attacks by American submarines and aircraft then obliged the Japanese to examine ways in which economies could be made. As part of this process it was decided that the supply of their forces in Burma should be via Bangkok instead of using the port at Rangoon.
This proposed re-arrangement of routes offered two specific advantages. In the first place it was appreciated that a saving of over 1,200 miles could be made if Rangoon could be replaced by Bangkok as the shipping terminus. Second, was also understood that the attacks from aircraft based in India which were already causing heavy losses to shipping approaching Rangoon were likely to intensify. Thus, a potentially safer and shorter route had much to commend it but the problem with implementing such a scheme was that there was no existing provision for the ongoing movement of cargo landed at Bangkok to be carried into Burma. For this to be resolved required the Thai and Burma rail networks to be connected which was, in fact, a matter which the Japanese had already examined in their pre-war planning. This had resulted in a feasibility study being commissioned in 1939 and 1940 which was completed by a civilian consultant named Kuwabara. His conclusion was that such a project could be finalized in a year if sufficient resources were availablebut given wartime constraints military engineers revised this estimate to five or six years.21
Japan had not ratified the Geneva Convention of 1929 but as it had signed The Hague Agreement of 1907 it was still legally committed to the principle that prisoners of war must not undertake work that would be helpful to their captors. In spite of this a decision was made to utilize the massive pool of labour which had become available after the fall of Singapore. It was, indeed, only the existence of this resource that convinced those in power that the construction of a rail link with Burma was a viable proposition. Thus, as early as March 1942 preliminary preparations were begun and British prisoners started to move to Thailand at the end of June 1942. At about the same time a large unit of Australian prisoners which had previously been employed to help repair the former British airfields in Burma was re-deployed to begin building the track towards the Thai frontier at the Three Pagodas Pass. Eventually, more than 60,000 British, Dutch, Australian and a few Americans were to be engaged in Thailand and Burma in constructing the rail link. It should be emphasized that all of this vast workforce were employed purely as unskilled labourers as all of the technical and skilled tasks were the responsibility of the estimated 12000 to 15000 Japanese who were allocated to the project.22 A further substantial number of labourers, perhaps over 150,000, were recruited locally and from the occupied territories but their high mortality due to tropical disease and the poor organization provided by their Japanese masters seems to have greatly limited their contribution to the work.
The net result of the activities of this diverse workforce was that in spite of appalling conditions including heavy rainfall, little medical provision and a complete lack of capital equipment the track was completed over a distance of 415 kilometres (262 miles) in just over eighteen months. This tremendous achievement owed much to Japanese ingenuity – many existing lines were cannibalized to obtain rails and machinery – and even more to a ruthless determination to ignore the human cost. Thus, it has been calculated that 20% of allied personnel died during the construction of the Railway. Over the same period only 4% of the Japanese engaged in the enterprise were lost – on the other hand at least 26% of the indigenous labourers failed to survive a single year23 and it is estimated that over 90,000 were eventually to die working on the project.
The extent to which this massive cost in lives can be justified by the military situation should now be considered. The original plan was for the Railway to be able to carry 3,000 tons per day but by the time it was completed this had already been reduced to a target of 1,000 tons. This revised figure was due to a recognition of the poor quality of the track and rolling stock which was accepted as being the best that could be expected in the circumstances of the time. In practice, even this lower throughput was seldom possible on account of the rising severity of allied air raids which led to much disruption and thus by 1944 the daily average was seldom above 300 tons.24 However, it should be appreciated that the Railway also transported large numbers of troops into Burma who would otherwise have had to march long distances with all their equipment. It is thought that these amounted to as many as seven divisions together with many Corps and Headquarters personnel. In addition, at least 10,000 casualties were evacuated via this route which later, after the abortive attack on India, was used by many units to withdraw into Thailand. The fact that these troops were able to retire in good order meant that they were soon able to set up a strong defensive position at the Three Pagodas Pass and had the war not been ended by events elsewhere they would undoubtedly have caused the British forces many problems.25
The delivery of men and supplies to Burma on the Japanese side was paralleled by comparable events on the British side. Following their retreat from Burma British army formations established new defensive positions along the Indian frontier. The need to supply and reinforce these troops presented a major logistical problem given the fact that there was no through road from the nearest port at Calcutta some 600 miles away. At first, a combination of rail, river and road transport which had been used to service the Assam tea industry was utilized but this could only provide 600 tons per day. By 1943, this figure had been raised to 2,800 tons but this was still insufficient to cope with the rising scale of operations. This logistical problem was not finally overcome until 4,700 trained railwaymen were brought over from the United States together with many powerful new locomotives which enabled the daily throughput to rise to 7,300 tons.26
When I mentioned these statistics to Yoshihiko Futamatsu in our correspondence27 he immediately asked for further details and I referred him to the appropriate source.28 He subsequently wrote to say that he now better understood the difficulties which needed to be overcome by the British in order to satisfy the needs of their forces which were similar to those faced by the Japanese. He also felt that while the British succeeded in raising their throughput to the desired level the Thai-Burma and internal Burmese railway systems were never able to meet the Japan’s military needs. This, he thought, was a major factor in Japan’s defeat at Imphal.29
The roles of Futamatsu and his friend and colleague Renichi Sugano in these events will now be examined. The former, born in 1912, studied engineering at Kyoto University where he specialized in bridge construction. After graduating in 1935, Futamatsu was employed by Japan National Railways until 1940. He was then called up and became a gunzoku (a Japanese military auxiliary) with the rank of Captain and a role as a consultant civilian railway engineer. This led to him being attached to the HQ of the 9th Railway Regiment where he met Sugano for the first time.30 The latter, born in 1919, entered Military Academy in 1938 and graduated two years later. He was then appointed as a Company Commander in the 1st Battalion of the Regiment with the rank of Captain.31
Subsequently, both officers took take part in the invasion of Malaya in December 1941. However, while Sugano landed directly on the Peninsular, Futamatsu arrived in French Indo-China prior to the start of the war and then moved into Malaya via Thailand when the fighting began.32 Sugano’s unit had the task of making temporary repairs to the track and bridges immediately behind the advancing troops while Futamatsu worked with the 4th Special Bridging Group which followed up constructing more permanent structures. When the Malayan campaign ended both were at first involved in the renovation of the colony’s rail network. Futamatsu subsequently joined the Southern Field Railway Group based in Singapore and was soon to be concerned with planning various aspects of the proposed Thai-Burma Railway. At about the same time Sugano moved into Burma where his Battalion helped to restore the damaged railway track before being re-deployed to Banpong in Thailand.
By then the HQ of the Southern Field Railway Group had been moved to Thailand where Futamatsu and Sugano were able
