The vast majority of the workers recruited in Malaya were ethnic Tamils. Their homeland was on the southern tip of India and parts of Ceylon (now known as Sri Lanka). The British Colonial government had moved thousands of them to Malaya generations before to work the rubber and sugar cane plantations. They found themselves to be little more than slaves. The British called them coolies. They were the lowest of the work force and social class in Malaya. [the history of the Tamil migration to Malaya will be told in Section 20] So, when the Japanese offered them employment in northern Malaya, many thousands packed their meager belongings and eagerly boarded the trains – many with their families in tow.
We have no records to relate precisely where the romusha worked on the TBR. From survivor accounts, we know only that they worked side-by-side in some places with Allied POWs. One additional source that identifies the various ethnic groups is the Thai-anusorn Shrine that has plaques written in their languages (Thai, Tamil, Vietnamese and Sumatran/Javanese).
The inclusion of these languages on this shrine are the only tangible evidence that the romusha workers included Vietnamese and indigenous people from the Dutch East Indies. These were possibly some natives of Java who were moved to Thailand through Singapore in the same way that the POWs captured on Java arrived at the TBR.[1] It is still unclear if there were truly romusha from Java or were these simply the Javanese conscripts into the Dutch Army (KNIL).
The Allied POWs were able to describe the large numbers of Tamil workers primarily due to their darker skin as compared to the other Asian workers. The Burmese sector was built by Allied POWs (to include the majority of the US POWs) along with native Burmese and ethnic Mon tribesmen.
There seems to be no doubt that the vast majority of the romusha were Tamils. Allied POWs suggest that up to 100,000 were utilized to build the Mergui Road in the summer of 1945. This is in addition to 120-150,000 that worked the TBR. Deprivation, disease and ill-treatment led to the deaths of about 20% of the 61,000 Allied POWs. It is estimated that the death toll among the romusha was 40% at a minimum!
The involvement of Thai laborers came to an abrupt halt in DEC 1942 in what is known as the BanPong Incident. (see Section 24)
[1] It is also worthy of note that the iron structure of the existing bridge = the famous Bridge over the River Kwai was stolen from Java and transported via ship and rail to be reassembled at ThaMaKam.