Pai Bridge

The bridge over the River Pai is often cited as the most conspicuous evidence of the presence of the Imperial Japanese Army
in Thailand during WWII. Unfortunately the statement is in error, as is much other information about that period . . . .


Japan in Northwest Thailand during World War II


Subject: The Japanese presence, especially that of the Imperial Japanese Army (IJA), in the northwestern Thailand provinces of Chiang Mai and Mae Hong Son, during World War II. That area, with a portion of Burma necessarily included, is shown with important features noted:


Map overall of northwest Thailand

The map mosaic is not artistically consistent throughout, but rather reflects the most useful sources for the two different countries involved.


Objectives: 1. Review some of the more accessible sources on the subject, which are, at this late date, almost all secondary; those sources include Thai, Japanese, and English language texts plus aerial photos, from both the period and subsequent retrospectives.
  2. Visit identifiable locations, record GPS info, take photographs, search out local information, particularly Thais (such few as have survived into old age and can be found) who can act as primary sources.
  3. Note conflicts amongst sources and attempt to resolve.
  4. Present results incrementally as obtained, in one language (at least initially), ie, English, and organized by geographical location, in this case, keyed to the current Thai highway road numbering system and stationing (see Table of Contents below).

There is no final word on this subject.

Much information is incomplete; many secondary sources remain untapped because of language barriers; conflicts remain unresolved; additional conflicts may have been unintentionally introduced both within the sources here explored and with other sources not reviewed. In some cases, subjects that do not appear directly related have also been explored to clarify information bearing on events in WW2.

This is intended to be a working document, relying on the flexibility allowed by an Internet presentation; it is not intended to be static with facts committed irretrievably to hardcopy.

Readers are encouraged to bring problems and new information to the attention of the author at;


Numbers refer to Thai Highway Routes
Unnumbered roads are prefixed with a T
Numbers prefixed with B refer to (Burma) Myanmar Highway Routes

  Introduction with graphical map index
  Area general history
  Chiang Mai City
  Chiang Mai Province
  Mae Hong Son Province
  Other locations
  Route Choices through Thailand for Invasion of India
  Primary Withdrawal Route to Chiang Mai:
    Burma connection: Toungoo - Kemapyu - Border Point 13 - Huai Ton Non - Khun Yuam
    Khun Yuam: Junction offering alternative trails to Chiang Mai:
      Northern Route: Mae Hong Son - Pang Mapha - Pai - Mae Malai - Chiang Mai
      Central Routes: Mae Na Chon - San Pa Tong - Chiang Mai
          Alternate Central Routes
          Original Central Route: The Old Elephant Trail
      Southern Route: Mae Sariang - Hot - San Pa Tong - Chiang Mai
    Other routes / points
  Appendices: Map Information, Summaries from Sources, Miscellany



Revision List
2010 Jun 11
First published on Internet
1 2012 Apr 30 Masthead photo changed. Content changed: a table of contents listing all subjects was replaced by a listing only of major subject categories with links to separate webpages providing subcategory breakouts. Single page table of contents relocated to "Annotated Table of Contents"
2012 Jun 10 Contents revised to be more "general"