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Chemical warfare


Chemical warfare had been a major issue during World War I. Not so much for the relatively limited amount of lethal casualties [estimates go as far as a mere 90,000] that it had demanded, but all the more as a consequence of the ethical and moral side that was attached to the massive use of poisonous agents (gasses and aerosols). The chemical warfare, particularly the use of lethal poison gasses, had horrified the ‘civilized’ world. During the early years of the interbellum initiatives developed to ban the use of poisonous gasses for application in warfare. Basically all the former WWI belligerents agreed that restrictions – or even a total ban – to the application of poisonous gasses was most desirable, but in fact all feared the abuse of an international ratified treaty at the same time. In fact, during the interbellum many thought that chemical warfare in a future worldwide conflict would be lifted to an even more devious level, particularly when even more ‘effective’ poison gasses were ‘invented’. Even today the inventions of the sort done in the 1915-1940 era trigger the world’s most important leadership, particularly during the last two decades when early 1900's invented agents like VX and Sarin were either feared to be used or actually used by terror states or terrorists.

The fear of chemical warfare also landed in the Netherlands, already during the early stage of WWI. When the first use of disabling gasses was reported on the East- and Westfront, that news soon reached the Netherlands. When shortly after the deadly poisons gasses followed, the Dutch army realized that it was not alone entirely unprotected and unprepared for such means of warfare, but that it too lacked the ability to strike back. It led to a hastily kick-start of a chemical warfare program, that was only briefly interrupted by the armistice of November 1918. It was the fear of potential treaty breach that kept the Dutch army actively developing chemical weapons and protection thereof during the interbellum.

This article describes the Dutch chemical warfare program and measures related thereto. A chapter that is often out of focus in WWII records, for after all the use of chemical weapons during WWII remained limited to Japanese acts against the Chinese. Nevertheless, almost all major belligerents in WWII had prepared themselves for chemical warfare and kept vast stock-piles of chemical weapons close at hand.

Introduction of chemical weapons on the battlefield

Chemical warfare is almost as old as modern people. It was already applied by the Chinese in the ancient history and also famous imperial armies like the Greek and Roman armies had forms of chemical weapons in their arsenals. Poison was a means that goes hand in hand with treason and treacherous acts. It has always been advocated as a symptom of unfair practises, but at the same time often proved effective nonetheless. Save the historical appliance of chemical warfare, it never saw such an unprecedented use as during WWI.

The massive use of poison agents during WWII went along with the chemical revolution of the 19th and (early) 20th century. Chemical plants developed during the 19th century as an independent new branch in world economics. The world was introduced to a vastly growing potential out of manipulated or fabricated chemical base-products. Future poisonous agents that were applied on the battlefields were basically derived from harmless civil use of the same or slightly modified regular products. Salt, sulphur, chlorine, ethanol and phosgene were commonly used chemical base-products as well as they would form the basis for poisonous battlefield gasses and aerosols. It were also these raw chemical products that boosted the quality of charges for explosives and shells, like picrine acid, that was originally ‘discovered’ during processes to develop yellow pigments for toys and domestic products.

Already during the last decades of the 19th century international agreements on restriction of chemical and biological weapons saw the light of day. Even in 1907 the The Hague Conference addressed the ratification of the previous agreements. How futile these agreements were, was demonstrated even before the calendar turned to 1915. Already in October 1914 the French and German armies applied disabling gasses (mainly tear-gasses) on the battlefield. In April 1915 the Germans were the first to apply a lethal agent, chlorine gas, on a large scale (after some minor experiments since January 1915) during a battle in the Belgian Ypres [Ieper] region. No less than 168 tonnes of gas were unleashed over the heads of the French colonial defenders at an area called the Graventafel. Around 6,000 French troops perished in a matter of minutes, partially from poison effects, but also from plain arms fire (chased out of the trenches as the victims were by the dense gas). The event was of paramount significance and set a landmark in the history of WWI, but also the chemical warfare in general.

The introduction of the lethal agents to the modern battlefield caused a revolution in the development of both offensive and defensive chemical warfare. All sides started applying the agents to the battlefield but at the same time developed countermeasures, like gas masks, filters, resistant anti-fluids, protective clothing and treatment methods. Also the means of delivery to the battlefield developed. The first containers had been trench held cylinders that discharged their lethal load born on the wind, but soon delivery by artillery shells, spraying airplanes or bombs saw introduction.

As the war developed measures and counter measures went along and the significance of chemical warfare – particularly on the strategic level – rapidly diminished. But even on the tactical level it soon declined as a measure of importance. Notwithstanding the introduction of severe lethal gasses like mustard gas and phosgene gas – in the years 1917 and 1918 used in large quantities – the significance of chemical warfare was no more (or less) than a nuisance for the manoeuvrability of the troops suffering such an attack. Yet, occasionally the crippling effect on formations was significant and it was particularly that aspect that would remain the main reason for continuous ambition of field-commanders to use chemical agents onto the battlefield, even in decades to follow. Moreover, the availability of these agents forced all armies in the world to be prepared, to maintain or build large stock-piles of protective means and at least a strategic storage of agents themselves in order to be able to counter the use by an opposing force. 

Dutch developments

The Netherlands being neutral during WWI were anxiously monitoring the rapid tactical and material developments on the battlefields around them. Particularly the trench warfare in France and the southwest corner of Belgian caught the attention of both military and civil authorities. Besides the amazing developments in respect of aerial warfare – where a true technical and material revolution was witnessed – the introduction of numerous new weapons and weapon-systems was anxiously witnessed too. The significance of the machinegun, long range artillery, the howitzer and mortar posed the Dutch military with a shear impossible challenge of keeping-up. Besides a few hundred available machineguns, the Dutch lacked long range arty, howitzers and mortars in their arsenals. But the introduction of lethal agents was even more terrifying for the Dutch army command. They had no knowledge whatsoever on this matter. It caused the Dutch defence apparatus to formally address the matter already within a month from the events in Ypres, after they had collected information in the weeks before.

The Dutch were primarily focussed on the development of two agents. The most important of the two was dimethylsulfate  The (at that stage) subsidiary choice fell on phosgene, even before it had been applied on the European battlefields. The reasons to select both agents was quite simple. The still very limited Dutch chemical industry was able to produce both media relatively easily as opposed to other agents, like chlorine or later mustard gas. The matter was quickly adopted by the commander-in-chef of the Dutch army, who demanded a rapid assessment of the Dutch production potential but at the same time extended testing of the means of delivery on the battle-field. Simultaneously the developments to mass produce protective clothing and particularly gas masks were taken up.

It was 1916 before the Dutch army had its first batch of trench cylinders available enabling the field army of small scale chemical attacks. Meanwhile the path of dimethylsulfate had been abandoned, mainly due to the hazardous process of production. The newly selected agent had become sulphur dioxide. Again a product that could be delivered by the limited Dutch chemical industry. Nonetheless the very limited volume of the Dutch chemical industry, that obviously had its ‘regular’ demand to fulfil, was hardly capable of producing anything more than some small volumes of agents enabling the field army to build up a storage capacity of a mere handful of gas attacks. It was already 1917 when the first amounts were made available. In the end there were by far more means of delivery (trench cylinders) available than agents to deliver.

Besides those material challenges there were the obvious defensive means of preparation. Obviously the distribution of gas masks – basically not much more than wetted cloths and goggles in first instance – but more particularly the training of field army units in the measures against a chemical assault. Gas officers had to be educated and forthwith instruct their units about the idiom of chemical warfare. Furthermore specific gas-companies were formed for the adherence of offensive chemical warfare. During these instruction and exercise processes much came down on improvisation and ad hoc improvements.

Meanwhile also the agent delivery matter hit the agendas again. It was soon learnt that the delivery of agents by means of artillery shells pushed the cylinder release application to the background. At first it seemed to be an easy fix to develop agent containers onto artillery shells, but soon enough the challenges popped up that had been overseen. First of all the ballistic issue obviously, but also the filling processes, the corrosion effects on the shell containers (by the agents) and last but not least the matter of adequate volumes to be delivered on the battlefield to sort any effect on the raided enemy positions. By the time the Dutch research teams had been able to work that all out, the armistice of November 1918 had become a fact. It temporarily stalled all funding and priorities.

By the armistice in 1918 the Dutch army had a massive backlog in the knowledge and development of chemical weapons along with the tactics and operational appliance. In fact the Dutch army capacity of chemical warfare was in the same rudimentary state that the belligerents had been in January 1915. Perhaps is was even worse. In the end all that was achieved were the availability of some thousands of trench containers, a very modest volume of agents and a still extremely poor means of personal protection for the men in the field.

The interbellum

After the announcement of the quite sudden and unexpected armistice of November 1918, which also liberated the Netherlands of the fear of invasion and the burden of a very effective Allied navy blockade, the chemical warfare agenda was closed. But not for long.

It was soon realized that the backlog in chemical warfare that was suffered had to be closed. Like other European nations, the Dutch were far from confident that a new European conflict could be ruled out for long. Generally spoken, the Dutch were all too aware that their neutrality during WWI had saved the country – and its generations – of devastation and paramount death-tolls, but at the same time that their military branch had missed out on a material and tactical revolution of unprecedented magnitude. One of the elements that wasn’t underestimated was the topic of chemical warfare. As a result of that consciousness the research on chemical warfare saw a rapid revival.

During the interbellum the international community showed great ambition to a world-wide ban on chemical weapons. Notwithstanding several agreements and treaties on the banning of the use of chemical weapons, the international community failed to certify a ban on the possession of the same. The significant international distrust amongst leading nations of stealthy stocks of agents kept by nations notwithstanding a ratified all out ban on chemical weapons caused the large armies around the world to maintain vast volumes of chemical agents in store. The Dutch position during the many chemical warfare convention meetings was one of the same ambivalence. The Netherlands did not trust the leading European nations to abandon their chemical weapons and moreover, the Dutch were very much aware that even when these leading nations would in fact abandon their stocks, that they would be able to rebuild those in no time compared to the Dutch. This political ambivalence was amplified by the military desire to research and develop chemical weapons despite any international treaty to disband those weapons. The military considered it of paramount importance to gain some ground in the knowledge of material and tactical chemical warfare.

In a weapon-strategic sense the Dutch took a clear position. It would not – in any circumstance – be the aggressive (first) user of a chemical agent in any conflict. It totally focussed on counter strategy as it came to chemical weapons. That counter strategy enhanced the defensive capacity (protection of personal, training and detoxifying measures) and the counter-offensive capacity. The latter implied the preparation for storage and use of agents coming available to the military once the opponent would have delivered the first strike. This position, which was both the military and the political attitude towards the issue, was the very reason why the Dutch government hesitated to ratify the 1925 Geneva protocol (of the Preparatory Commission) on the use of chemical and biological weapons. The Dutch had undersigned the treaty but were reluctant to ratify as long as the major participants in the treaty hadn’t done so yet. Only in 1930 the Netherlands finally yielded to international pressure. Yet the protocol on the use of chemical and biological warfare was not a total abolishment of these weapons, but more like a conditional restriction.

Parallel to the gradually tilting political tendency towards ratifying the Geneva protocol, the Ministry of Defence started choking the research and development request from the military. It was finally decided that the Dutch army would not produce and store vast volumes of chemical or biological agents, whereas at the same time small scale R&D remained permitted. Nonetheless, the artillery demands for gas-containing shells were put on such a low priority scale, that it would be quite accurate to define these developments as close to none. Although designs for main gun type gas-projectiles [7-veld, 10-veld, 15 cm Krupp howitzer] were available, they seem not to have been tested, although there may have been some marginal testing on the 7-veld gun projectiles, which had been in focus since 1918 already. When push came to shove the war stocks of the Dutch artillery shells contained not a single gas projectile in 1939/1940.

Meanwhile the development in the agent selection area had not ceased. During the late twenties the agents selected for chemical warfare were of the types chlorine picrine and chlorine arsine, although phosgene and mustard gas remained in focus too. In 1928 the Dutch defence industry main plant – the Hembrug at Zaanstad – facilitated (next to the existing chemical lab) a genuine research and test lab on the production of agents on its own premises. Test installation (scale models) were designed and constructed and actually started up. These tests were not simply means of research for potential indigenous production of agents, but also intended to produce these toxic gases in order to test the defensive devices which were under development, such as filters (for rooms and vehicles), gas masks (for men and horses) and protective clothing (against blister-causing agents like mustard gas). Besides those defensive and offensive issues, there was also the issue of legal chemical ammunitions, like smoke generating ammunitions and tracer ammunitions. All these issues were concentrated in basically one single military material branch, operating from one large research lab and one research and test lab for production and testing purposes.

One of the unavoidable aspects of the issue of chemical agent production was the involvement of the indigenous chemical industry. When in 1930 a confidential letter was issued to all the chemical plant owners, it was a matter of time before the confidentiality would be broken. Particularly in those days of strong felt pacifism and political segregation there would always appear a leak somewhere. There where the defence industry (which was nationalized in the Netherlands and a subsidiary of the Ministry of Defence) was working in the twilight zone of its mandate, the disclosure of the inventory request by at least one approached chemical plant owner caused Dutch parliament members to get word of the actions by the defence industry. A communist MP confronted the Minister of Defence with embarrassing questions on the matter. Subsequently a Dutch newspaper printed the integral text of the inventory letter in one of its editions, which did not only cause the total disclosure of the matter but also that – without any doubt – the letter caught the eyes and ears of the ever active foreign intelligence services. And that all in the exact period of time that the Dutch were in the (political) process of ratifying the Geneva protocol!  In the end the Dutch parliament was satisfied with the reply by the Minister that some degree of preparation in the form of small scale tests and probing of defensive equipment was imperative for an army that should be prepared for an enemy who would possibly make use of chemical warfare, also in the vast Dutch colony (the Dutch East Indies).

The inventory of the Dutch national capacity for the large scale production of chemicals was disappointing. In 1931 the final books were made up and proved that the production capacity within the main defence area of the country [roughly the region north of the Maas and west of the city of Utrecht] was neglectable and on a wider scope (the entire country) still minimal. Moreover it turned out that the existing chemical processes in the indigenous chemical industry hardly involved any of the required base chemicals needed for battle agents. The outcome of the inventory meant – in fact – the bankruptcy of the Dutch strategy not to store vast volumes of agents beforehand but the preparation of a role out for an emergency production plan for battle agents in times of high international tension. The existing Dutch chemical industry branch simply did not allow for such a strategy. It came down to either predetermined storage of the large volumes needed or abandon the idea of production whatsoever. The only ‘fix’ that could present a modest middle-way was the storage of large volumes of base-chemicals (required for agent production) and upgrading the chemical industry proactively in order to make the transformation of civil processes into military processes a matter of days rather than months. Obviously that middle-way solution demanded extensive funding, which was lacking. It caused a stand-still in the issue of agent production in the Netherland for at least five years.

It was 1936 when some new developments were seen. The shocking world-wide crisis and the rise of the Hitler regime had caused chemical companies who had some years before shown considerable reluctance to cooperate, change their attitudes anxious as those companies were to prevent war and more particular, earn a penny or two. Although the position of the chemical industry had also improved some in a technical sense, the issue of indigenous production would not come to a solution. As off 1938, when it became clear that other issues, like the dangerously empty regular ammunition stocks of the army, had grown in importance over the already twenty years long dragging issue of agent production in the home country. Twenty years of virtual stand-still …

That in fact in 1939 true mustard gas would be produced in the Netherlands, was (is) unknown to many. How it came to that (weighing the aforesaid) unexpected production, shall become clear when the chemical warfare dossier in the Netherlands East Indies is addressed hereunder.

Protective equipment and personal gear

There where the political issues were quite easily repelled by the military leadership, another much more challenging issue grew. The emphasize of the military defence industry had been much more on the challenges faced in the production side of chemical warfare than on the protective (passive-defensive) side. Already during WWI the Dutch army wouldn’t have had a chance of surviving intensive chemical warfare tactics. The passive defence against chemical agents had far from approved.

On paper the Dutch had an army strength (homeland army) of around 400,000 men. All these men had to be fitted with a personal gas mask at least, and preferably protective clothing to (a necessity in the defence against most nerve-gasses and blister-gasses). Also a large supply of spare filter busses for the gas masks were necessary as well as precautions to filter rooms (such as staff rooms, hospitals, etc.), shelters (both civil and military) and if possible a considerable percentage of the cavalry and artillery horses. Aside from the personal gas-masks, none of the other means were available in 1930, but even gas masks were not available in sufficient numbers. No more than about half the army could be supplied with gas-masks and then again, a considerable share of those available lots were write-offs or insufficient in their protection against modern G-type (nerve-gas) agents. The chief of staff and the commander of the field army wrote a letter to the minister demanding urgent action.

The appeals from the military leadership had some effect but by far too little to improve much and – in particular – fast enough on the position of passive protection. In the end they managed to come to an agreement with the ministerial staff to recover the lacking stocks in 1936. The funds for such a recovery had to come from the total budget for chemical warfare (which were considerable in relation to the total defence budget). It was only with hesitation that a mild raise of funds for passive defences were raised – by far not enough to overcome the gigantic backlog in supplies.

Developments in the Netherlands East Indies [NEI]

A different approach in the East Indies

The Netherlands were still in 1940 a nation that reigned over several colonies, like The Netherlands Antilles and Surinam in the West and the vast territory of the Dutch East-Indies in the East. The latter nowadays better known as Indonesia. The colonies were governed as a separate and more or less autonomic entity. A minister of colonies existed in the Dutch (home) cabinet to look after colonial affairs. That minister had quite extended autonomy and was more or less the prime-minister for the colonies, even to such extend, that domestic decisions on defence had no extension to the colonial defences. The latter were the sole responsibility of the minister of colonies for as long as he stayed within his budgets. It was only when substantial matters of political of military nature had to be governed that the Dutch cabinet and parliament had a decisive say in things. That had been the case when large investments had been done for the KNIL air force and the Dutch navy in the colonies. The latter had seen an ambitious cruiser-plan accepted by parliament, just before war break-out, providing the Dutch navy with three battle-cruiser (28,000 tonnes, 9 x 28 cm main battery). Obviously those plans never materialised due to the German invasion of the homeland.  

This autonomic structure was applied for the army too. The Dutch army – and the commander-in-chief (in peace time the chief of staff of the army was the most senior in function) had no say whatsoever as to the matters overseas in the East Indies. The West Indies were military-wise ruled by the Navy Staff and the East Indies had their own army, the KNIL [Royal Netherlands East-Indies Army]. This KNIL army was entirely made up from professionals, but had an expansion scheme which included the forming of militia from indigenous personnel and a small reserve of Dutch reserve officers. The army and navy in the East were totally independent of the home country as it comes to military matters. The Governor of the East-Indies and the Minister of Colonies jointly formed the governmental authority.

The East Indies were in fact much more liable for a potential enemy that would apply chemical weapons on the battlefield than the home country. Obviously that is knowledge in hintside. Nevertheless, it was the empire of Japan that would actively use agents during WWII (mainly in China) whereas none of the other belligerents in WWII would use a single device. Another issue that was substantially differentiating from the home land affairs, was that Japan already showed an unhealthy interest in the riches of the Dutch East Indies as early as the turn of the decade (twenties, thirties). And when Japan started its first aggression in the Chinese hemisphere, it became apparent that the Japanese ambitions were very vivid. In the homeland the awareness of a genuine threat from the eastern neighbour only started to land around 1936/1937.

The developments towards chemical warfare researches in the East Indies, started much later than in the Netherlands. The KNIL had only taken its first steps towards chemical warfare in the late twenties. That late start made a lot of sense. WWI had largely passed by without significant conflict in South-east Asia and moreover there were no aggressors in the region possessing – let alone applying – chemical weapons. Japan only started its chemical warfare program in the early twenties. The KNIL totally relied on the limited homeland research outcomes as it came to chemical warfare. And from those limited fruits rose the impression that most agents would be less effective or not effective at all in the warm and humid tropics (whereas gasses tend to have extreme low boiling points they quickly disintegrate or disperse as temperatures rise). Only later it turned out that on the other hand the nerve gas agents were all the more effective in the tropics, thriving on the moist of sweaty skins.

There were two aspects leading to independent KNIL research and development of chemical weapons. The first was the meanwhile inevitable development of such weapons in the reason, particularly Japan. The second was that chemical agents seemed appropriate means to repel local uprisings. One has to realize that in the last century (before 1940) alone the Dutch had fought at least about thirty major uprisings or even genuine wars. For example the province Atjeh [‘Aceh’ in Indonesian] – the northern part of the island Sumatra – had caused the Dutch numerous challenges. Traditionally the indigenous tribes opposed their occupational masters. Before the British Empire (in 1871) had ‘granted’ the Dutch the rule and ownership of the strategic province (as a strategic decision, forcing the Dutch to counter the thriving piracy around the commercial sea-routes), the local tribes had fought the British occupation. In the late 19th century the Dutch fought a straight out war in the region, lasting no less than 30 years [1873-1904]. In that era several military campaigns had demanded large sums of money and quite extended death tolls. But also elsewhere local uprisings, some bigger some smaller, caused the relatively limited colonial army to deploy important forces in the outskirts of the vast archipelago. The possibility to apply a chemical agent as a means of suppressing uprisings was therefore seen as an opportunity of unique proportion. It should be said though that the focus for these policing application was mainly on disabling agents rather than lethal agents.

In contrast with the Dutch homeland situation, where politicians and military top-brass went quite convincingly along in their mind-sets – the KNIL leadership found itself tempered by the Governor. The latter was reluctant to release any fund to chemical warfare – offensive and defensive – as long as the directive out of the Hague offered him no decisive guide. It went even so far that gas officers [officers specializing in gas protection and defences] were no longer trained. The Governor obviously interpreted the concept of the Geneva protocol much more rigid than his superior in the Hague and he wasn’t adjusted by the minister of colonies. Yet, quite soon after, the funding of developments regarding passive defence against chemical weapons was released after all. It resulted in procurement of new protection gear and the founding of some research facilities in the Indies.

During the thirties a more aggressive approach towards offensive chemical weapons occurred. The KNIL desired to have a bulk storage of chemical agents to retaliate on the use of such means by a future aggressor, specifically mentioning Japan. Although the matter had already been addressed in the homeland and resulted into the ‘typical’ Dutch approach not to store large volumes of agents but prepare the indigenous industry to produce those in times of international tension, the same Dutch government weighted the Indies situation quite differently. It was also clear to them that Japan not ratifying the Geneva protocol incorporated the undeniable risk of that country actually applying chemical weapons in practise. That was all the more feasible in the light of the uncamouflaged Japanese expansion ambition. Nevertheless, in the end the cabinet lacked the courage to sanction the KNIL request to build an adequate storage of chemical agents and instructed them to copy the Dutch fix to have the chemical industry prepare for an emergency production scheme in case of international tension. Meanwhile – and in contrast to the homeland situation – the amounts of agent base chemicals procured for ‘testing and probing’ had mounted to interesting proportions.

The development of KNIL initiatives to build a war-supply of chemical agents was suddenly boosted by the international incident that arose from the Japanese-Chinese war, where China filed a formal complaint against Japan on the use of lethal agents. It was 1937 and time was ticking. The KNIL demanded the construction of a scaled mustard gas plant in the East Indies for extensive testing of both the (manufacture) process and the passive defence against that particular agent.

The Dutch defence industry [Hembrug] works got the request from the KNIL, they were highly motivated to adhere. The same team struggling with the ever dragging homeland discussion on the issue, secretly designed and constructed a scaled test-plant at the factory premises in Zaanstad, which was eventually capable of producing effective mustard gas. Although the quantities were modest (proof of around 1 ton of mustard gas is found), it was the first true quantity of this nerve-agent actually being produced on Dutch soil. As secretly as the Hembrug team operated not to disclose their secret to the governmental authorities, it were Dutch officers of the homeland army enjoying the long awaited experience with the production and characteristics of mustard gas. Around 1 ton of mustard gas was produced, perhaps a little more. After the process had proved itself, the entire plant was dismantled and shipped to the East Indies, where it was rebuilt on a military terrain at Batujajar [near Bandung, West Java] in 1939. Together with the scaled plant, Hembrug delivered tonnes of base chemicals to feed the process. Five underground storage tanks provided for a volume bulk of 65 tonnes of mustard gas, but it is almost certain that at least around 100 tonnes were produced before in 1942 the Japanese invaded the East Indies. Those 100 tonnes were sufficient for a modest number of chemical assaults, but by far insufficient for extensive appliance of chemical agents. Nevertheless, it is a fact that the Netherlands East Indies possessed a (modest) volume of battle-ready chemical agents of the lethal kind.

How would the gas be delivered onto the battlefield? The Batujajar plant side had a filling stations for (aerial) bombs, probably of the 300 kg type that were carried by the KNIL air force B-10 (Glenn Martin) bombers and/or for large volume spraying tanks. The filling station and the storage rooms were connected by rail-lorry tracks, indicating that indeed heavy containers (like bombs or large airborne spraying containers) were used. Proof of the exact devices used (or foreseen to be used) fail. It is certain though that Curtiss Wright CW-22 Falcon [light single engine trainer] were prepared for spraying operations. These planes have been seen with aluminium spray-installations in Andir [Bandung, Java]. Mechanics have been trained in the handling of mustard gas and the use of full protective clothing. It is generally accepted – although not proven – that also gas containing artillery grenades existed. They remain untraceable in the records though.

During the three months war of the Netherlands East Indies with Japan [8 December 1941 – 8 March 1942] both sides refrained from using chemical agents (other than smoke generation). One peculiar detail against that may not be left out though. On the 1st of March 1942, when the last tunes of war were sung by the KNIL, the squadron of CW-22’s were suddenly fitted with the spraying tanks while orders were submitted to fill these tanks with mustard gas. It is uncertain whether intentions were to apply the gas on the Japanese invasion force ‘as a last desperate act’ or whether the intentions were to spray the gas across the ocean to prevent it from falling into Japanese hands. Certain is that about half the stored volume was destroyed by the KNIL, which indicates that indeed the thought of not letting it fall into Japanese hands may have been the reason to fit the designated squadron with the spray-installations. It can nevertheless not be ruled out that some impulsive action had been on the verge of happening when somewhere down the line a wise man decided to call the thing off. It can be ruled out though that any use did occur. The Japanese would have been overjoyed to announce to the world what ordeal had come upon them, particularly in the light of the Chinese accusations at the League of Nations in 1937.


The Dutch approach toward chemical warfare is a perfect example of ambivalence all along. At the same time it wasn’t – in this instance – not so much a matter of funding, but more a matter of ethics and probably in particular a matter of failing resources. It is tempting to conclude that the Dutch not having a considerable volume of battle-ready agents was more a reason of a failing supply-chain than a matter of ethical superiority and/or failing funds.

The military and the government both realized that preparation for chemical warfare was imperative rather than a subjective choice, like it was with other weapons of war. Chemical and biological warfare was in fact the first subject that called for a strategic decision of possessing such a means of warfare over the decision to actually apply those means. In a way it was the start of an arms-race that would see an unprecedented revolution as off 1945, when the first atomic bomb was used. The matter of prompt availability dominated the matter of use. The Dutch realized this during the last stages of WWI and the interbellum. It was probably the reason why – notwithstanding surreal chocking of defence funds during the interbellum – funds were continuously made available to at least endeavour gaining some knowledge and possibly a thoroughly prepared production plan for when the circumstances demanded a rapid development of adequate stocks.

Save the aforesaid it may also well be the case that funding was a major issue anyhow. Not directly – as proven by the quite substantial money-flow for chemical warfare in general – but indirectly. Particularly in the first decade after the great war, the Dutch were temped to think that investing large scale in chemical agents, could facilitate for a cheap compensation for a relatively small and poorly equipped army. The idea was briefly embraced that perhaps a potential enemy would think twice before invading a country that could (not necessarily ‘would’) counter an invasion by applying a massive poison gas offensive against the aggressor. Chemical warfare as a strong deterrent fitted right into the Dutch approach of armed neutrality for the lowest possible price.

During the second half of the interbellum, when the ideas of chemical warfare as a deterrent had faltered and the hopes for an industrial miracle production in case of crisis had shattered too, the typical total neglect reappeared. The neglect that caught the entire Dutch army during the interbellum, but that could have had a devastating effect once it would have come to German use of lethal gasses. In May 1940, when the Germans massed across the borders with the Netherlands, the Dutch army wouldn’t have stood a chance of cooping with a massive chemical warfare component. The troops were extremely ill prepared, many formations lacked even basic protection and facilities and trench-systems had not been prepared whatsoever. Fortunately WWII in Europe would remain a clean conflict, as it came to these chemical weapons. But the results of utterly irresponsible policies on passive protection against lethal agents – totally given in by ministerial dismissal of military demands on those means – could have been disastrous.

In the Netherlands East Indies the KNIL leadership showed itself much more determined than the homeland top-brass. The colony obviously profited from its remote position by sub-siding red tape and pushing the right buttons beyond the ministerial chain of command. Not only did the KNIL take care of their own – by assuring that adequate means of passive protection against lethal agents were available for the entire regular army – but also they managed to produce at least a modest supply of agents too. And they achieved such in less than five years time, whereas the homeland equivalents had used twenty years to achieve nothing else but burnt up time and efforts. In the end the only agent volumes produced in the homeland, had been a result of KNIL initiatives to construct a scaled production plant.

All in all the Dutch military had played a minor role in the history of chemical warfare (up to and including WWII). In May 1940 the Dutch army was ill prepared as it came to passive protection against the use of chemical weapons, but utterly unprepared and toothless as it came to the aspect of offensive chemical warfare. The Dutch colony in the East was in a considerable better shape, particularly when it came to passive protection matters. The modest supply of around 100 tonnes mustard gas wouldn’t qualify the KNIL as offensively prepared, but at least it had some bite available in case it would be bitten first.

Epilogue – recognition

This narrative about the chemical warfare in the Netherlands (and its empire) during the first half of the twentieth century has been much supported by the excellent and very extended study of Herman Roozenbeek and Jeoffrey van Woensel [‘De geest in de fles – de omgang van de Nederlandse defensieorganisatie met chemische strijdmiddelen 1915-1997’, ISBN 978-94-6105-102-8, Boom publishers] under the wings of the Dutch Institute for Military History. The comprehensive article hereabove wouldn’t have been possible without the thorough research of these two men.