What happened
The Imperial Japanese Army built the line — about 415 km from Ban Pong in Thailand to Thanbyuzayat in Burma — between June 1942 and October 1943 to supply its Burma campaign. It was built with forced labor: over 60,000 Allied prisoners of war and a far larger number of Asian laborers (romusha), commonly estimated at 200,000 or more, though estimates vary widely. More than 12,000 POWs died, along with tens of thousands of Asian laborers — estimates run to 90,000 or higher. Hence the name Death Railway.
Background
After Japan’s advance into Southeast Asia, sea routes to Burma were exposed to Allied attack, and a land link was needed. Thailand under Phibun had aligned with Japan through the December 1941 alliance, and the line’s Thai section ran through Kanchanaburi province.
Consequences
After the war, camp personnel were tried for war crimes, and Allied war cemeteries were established at Kanchanaburi. The bridge over the Khwae became world-famous through a 1957 film — a fictionalized account. The Hellfire Pass cutting is now a memorial site, and part of the line still operates between Bangkok’s western lines and Nam Tok.