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Intelligence Gathering & Jujutsu - Part 5 - Japanese Fishermen & the Dutch East Indies



To understand the breadth of Japanese intelligence operations during the period of the Empire of Japan, let us consider their interaction with the Netherlands East Indies from around 1914 through to 1942.  We see here the massive scale of the Japanese intelligence machine at the time and the long-term vision of those committed to their cause.

Japanese Fishermen as the Vanguard of the Navy

A few thousand Japanese fishermen acted in and about the Netherlands Indian seas as forerunners of Japanese expansionism and as auxiliaries to the Japanese Navy...  Admiral Nobumasa Suetsugu, formerly commander of the combined Japanese Navy, subsequently Minister for Home Affairs, declared... that these fishermen had an important task to fulfil in the Japanese march towards the south.

...Already in 1914... they took up a threatening attitude against Netherlands rule, especially on the island of Dobo between Timor and Australia.  On the expert advice of the Japanese Naval Staff, they established themselves by preference at strategic points, such as the straits between Australia and New Guinea, the North East corner of the Celebs, the Island of Borneo near the entrance to the Straits of Macassar, and Singapore.

...Repeatedly they were found to make suspicious soundings and charts.

The places they established themselves were regularly visited by Japanese naval officers, especially those stationed at Palao, the capital of the Japanese Mandated Territory.  On different occasions, it was found that these fishing people placed themselves in territorial waters at the disposal of the Japanese Navy to collect maritime data and generally to do intelligence work.

At Macassar it was observed that Japanese boats went out not to fish but to communicate with Japanese vessels on the high seas...

Systematic Expansion Through Government Concerns

Fisheries were not the only means by which economic penetration with political and military intentions was attempted.  The part was also played by agriculture, forestry and mining.  Under the auspices of the Japanese Government, or of concerns which were controlled by the government, enterprises were started - some profitable but mostly unprofitable - subordinate to expansionist and imperialistic policy.

The first Japanese Colonisation Company in the Netherlands Indies, the Oriental Development Company (Toyo Takushoku Kabushiki Kaisha) made its appearance around the year 1920 and was followed by several others.

The company, in which the Japanese Government has a preponderant vote, and the Managing Director of which is appointed by the Government, has principally distinguished itself in Japanising all branches of agriculture, commerce and industry in Korea and also by acquiring land in Manchuria...

Subversive Action in the Naval Base at Sourabaya

One of the principal centres of espionage was the naval base at Sourabaya.  Several Japanese firms were made to employ clerks who had no other work than to obtain information for the Japanese authorities.  These spies had been trained for their profession at an institute which resorted under the Ministry of Foreign Affairs and was managed by Dr Shumei Ogawa who had already shown himself experienced on the subject when he was in the employ of the South Manchurian Railway Company.  The Nanyo Warehousing Company of Batavia had an employee by the name of Naoju Aratame whose exclusive task it was to spy and who, at a later date, was transferred to the Batavia Consulate General.  At Sourabaya these spies were employees of the Tekenokoshi Trading Company, the Daido Boeki and the Mitsui Bussan Kaisha...

Propaganda for the Preparation of the Invasion of the Netherlands Indies


  • Invasion of Japanese Merchandise, in 1931.
  • The March to the South (the 'Pan-Asian' movement driven by the Japanese).
  • Financial Support to Indonesian Traders.
  • Action Among Native Students (including offering education in Japan)
  • Propaganda Among the Islamites.
  • Influencing the Native Press.
  • Malay and Chinese Propaganda Journals.
  • Incitement Among Native Politicians.
  • Whispering Campaign.
  • Radio Propaganda.

Direct Preparations for Invaision by Japanese Government Departments

Federation for the Liberation of South East Asiatic Peoples... this organisation founded on December 19, 1940, is the most recent of those which pretend to aim at the liberation of the oppressed people in Asia.  The founders include Admiral Takeshita,... and Dr Shumei Ogawa who as previously mentioned is head of the Institute for the training of spies...

So Japan has for years made preparations for an attack on the Netherlands Indies, only awaiting a favourable moment...


  • Anti Netherland Press Campaign.
  • Consular Machinations to Undermine the Authority of the Netherlands Indian Government.
  • Preparations for the Transfer of Authority.

The above is taken from 'Ten Years of Japanese Burrowing' which is available from Archive here.  The photograph at the top shows oil fields at Tarakan (on Borneo / Kalimantan) in the 1940s. I have used spellings of names and places as they appear in the original text.


To summarise the actions of the Japanese with regards to the Netherlands East Indies, around 30 years before an open conflict, fishermen began establishing themselves at strategic locations and assisting the Navy with intelligence, logistics and political excuses.  This was rapidly followed by government-supported businesses of all sizes who secured resources, formed a loose intelligence network, gathered information and built connections with locals.  Larger businesses provided cover for professional spies and their movements.

In typical Japanese fashion, a large network of agents was created and the groundwork laid with the local population with a long-term view to securing the much-needed resources of the area and eventually political control.

This pattern had already been more than successful for the Japanese on the Asian mainland.




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