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It was July 4th, 1944 in London and the end of the war in Europe was finally in sight. The previous month, the Allies had liberated Rome and landed in France. In the east, the Soviet Army was rapidly advancing, crushing the German Army Group Center in Belarus and pushing towards Polish territory. Nazi Germany was far from finished and London was throughout the summer of 1944 being pounded by German V1 flying bombs, but the writing was clearly on the wall.
As these events unfolded, the commander-in-chief of the Polish armed forces, Gen. Kazimierz Sosnkowski, dispatched a brief report to his superior in the Polish government-in-exile, Prime Minister Stanisław Mikołajczyk. In September 1939, Nazi Germany in collaboration with the Soviet Union had invaded Poland and divided the country in accordance with the Molotov-Ribbentrop Pact. The following years the Poles would suffer grievously and most Polish Jews would be killed in the Holocaust. Despite this, the Poles had resisted the enemy occupation from the beginning and a Polish government-in-exile had been formed in 1939, which rallied the support of most Poles abroad and in Poland. As commander-in-chief, Sosnkowski was responsible for the Polish armed forces under allied command (195,000 personnel) as well as the main Polish resistance movement — first called the Union of Armed Struggle (Związek Walki Zbrojnej) in 1940 and two years later renamed the Home Army (Armia Krajowa). Sosnkowski’s report was about combat operations conducted by the Home Army in May 1944. The report detailed, among other things, sabotaging railways and communication lines and the targeted killing of 169 Gestapo officials. It then mentioned the following: “Poisonous agents were used in 766 cases, 87 poisoned parcels were sent, and 745 letters contaminated with bacteria were sent.”
The Polish use of chemical and biological warfare was nothing new. It began in the spring of 1940 and had only escalated throughout the war. The Western allies knew about this and during a state visit to the Soviet Union in December 1941, then-Polish Prime Minister Władysław Sikorski attempted to impress Soviet leader Joseph Stalin by highlighting the Polish war effort against the Germans, including the use of biological weapons. Between April 1943 and July 1944, the Home Army carried out 6,410 attacks with chemical and biological weapons. Nonetheless, the use of chemical and biological warfare against Nazi Germany was a tightly kept secret and it remains largely unknown today. So does the fact that Sosnkowski almost 20 years earlier – in Geneva in May-June 1925 – had played a key role in negotiating the Geneva Protocol, which banned the use of chemical and biological weapons in warfare.
This year marks the centenary for the signing of the Geneva Protocol, which remains in force today. Together with the Chemical Weapons Convention of 1993 and the Biological and Toxin Weapons Convention of 1972, the protocol comprises the lex specialis prohibiting the research, development, production, stockpiling, and use of such weapons. Sosnkowski participated in the negotiations and insisted on including biological warfare in the Protocol. So what happened between the conference in Geneva in May-June 1925 and July 1944, when Sosnkowski wrote his short report to the Polish Prime Minister in bomb-damaged London?
Unraveling this paradox is not an easy task. To make sense of it, this analysis proceeds in five sections. First, it returns to the origin of the Geneva Protocol by examining the role that Sosnkowski played in its creation. It then explores the complex — and at times seemingly contradictory — Polish stance on biological warfare. On the one hand, this stance led to the Polish contribution to the Geneva Protocol. On the other, it laid the groundwork for Poland’s own biological weapons program, which was particularly geared toward unconventional warfare. The third section discusses the consequences of these developments during World War II, when chemical and biological warfare became a part of the Polish underground’s struggle for national liberation. Afterwards, it traces Sosnkowski’s involvement in the events. The conclusion offers a critical discussion of the legality of Poland’s use of chemical and biological weapons — and whether such a legal framework makes sense when faced with invasion, occupation, and genocide.
The Birth of the Geneva Protocol
Strictly speaking, the protocol was a byproduct. In May and June 1925, leaders convened in Geneva for the Conference for the Supervision of the International Trade in Arms and Ammunition and in Implements of War under the auspices of the League of Nations. That ill-fated international organization was then only five years old. The goal of the conference was to finalize a convention on the regulation of the arms trade, which many believed had played a role in the outbreak of World War I. Even though the United States had not joined the League, Washington sent a delegation to the conference headed by Rep. Theodore E. Burton. In his opening address, Burton proposed to modify a draft of the convention to include the prohibition of trade in “asphyxiating, poisonous or other gases, and all analogous liquids” used for chemical warfare. Although enjoying widespread support, Burton’s proposal faced obstacles, like how to distinguish between chemicals for peaceful purposes and chemicals for warfare. Instead, it was proposed to make a universal prohibition on chemical warfare. A month later, a draft proposal for a protocol prohibiting chemical warfare was presented.
It was at this moment that Sosnkowski, the leader of the Polish delegation, took the floor. He was an imposing man as the Polish resistance fighter Jan Karski later described him: “Sosnkowski was a tall, tough, military type of man (…) He had unusually piercing blue eyes.” Sosnkowski had since his youth struggled for restoring his country’s independence alongside his friend and Poland’s future head of state, Marshal Józef Piłsudski. During World War I, Sosnkowski led Polish forces against the Russians under Austro-Hungarian command. Following the resurrection of Poland in 1918, he was hailed for his abilities as a military innovator and for obtaining French military assistance to modernize the Polish army. He was also one of the negotiators behind the Treaty of Riga, which ended the Soviet-Polish war of 1919–1921. By 1925, he was an accomplished officer and an experienced diplomat with a strong charisma.
From the beginning of the conference, Sosnkowski had proposed that any ban on chemical warfare should also include “bacteriological” (i.e., biological) warfare. In his speech, he remarked that the draft protocol did not discuss a prohibition on biological warfare and suggested to rectify this mistake. He highlighted that biological warfare could be conducted by secret agents “with far greater facility” than chemical warfare. An agent could cause havoc by unleashing a pathogen carried in a “small test tube or receptacle.” As he remarked, “The progress of modern science does not offer us any adequate means of combatting such a scourge, and the result will be that if it is employed we shall witness the wholesale extermination of great masses of the human race.” The speech achieved the desired result and biological warfare was included in a new draft protocol. On June 17, the draft was approved by the conference.
The decision to prohibit chemical warfare made sense in view of the widespread use of poison gas in World War I and the growing concerns that future wars would see even more widespread use of chemical weapons, especially when used in combination with heavy bombers to attack vulnerable cities. By contrast, the prospect of biological warfare was largely viewed as a future threat by a panel of international experts asked by the League of Nations in 1923 to evaluate the potential of chemical and biological warfare. As the Danish professor Thorvald Madsen wrote, “microbic warfare” could not — for the time being — be regarded as of real importance, although future scientific discoveries could change this assessment. He and the other authors of the League report were, of course, wrong. Biological warfare had been employed already. German saboteurs had used biological warfare sabotage against farm and transport animals in World War I and one of the League of Nations’ experts even mentioned the discovery of German biological sabotage material at the German embassy in Bucharest in 1916 following Romania’s entry into the war. There is also evidence that France used biological sabotage in 1916.
Poland and Biological Warfare in the 1920s
From a Polish perspective, the danger of biological warfare was here and now, although the Polish military was also keenly aware of the ills of chemical warfare. Poland did not exist as an independent country from 1795 until the end of World War I. During its six wars for independence, Poland also had to contemplate the risk of chemical warfare — especially during the Soviet-Polish War, which brought Bolshevik forces to the gates of Warsaw in the summer of 1920. German forces used chemical weapons against the Russian army in 1915 on Polish soil and during the Wielkopolska Uprising, German forces employed chemical weapons against Polish insurgents.
The Polish interest in biological warfare was likely due to several factors. During and after World War I, eastern and central Europe experienced waves of epidemics. The Polish government registered 673,000 cases of epidemic typhus with 141,500 deaths in 1918. Poland was also hit hard by the 1918 “Spanish flu” pandemic and by a typhus and cholera epidemic in 1920. Sosnkowski himself fell ill with the flu and his 10-year-old daughter died during the pandemic.
The new Polish state was weak and divided. It was also undermined by the presence of hostile minorities, who felt no allegiance to Poland and were used as pawns by external powers. One of them was Lithuania, which after a bloody war with Poland hoped to use the supporters of the so-called Belarusian Democratic Republic to destabilize its neighbor. Several small-scale attacks were carried out and Polish military intelligence (the Second Department of the General Staff) found evidence that Belarusian insurgents planned to assassinate high-ranking officers, poison water wells and food supplies, and use bacteria (Burkholderia mallei) against Polish army horses. No actual attacks with poison and bacteria seem to have occurred.
Another threat came from the Ukrainian Military Organization and later the Organization of Ukrainian Nationalists. Both movements wanted to achieve an independent Ukraine, which would also include large amounts of Polish territory. It is probably telling that the Ukrainian insurgents were supported at different stages by German, Lithuanian, Russian, and Czech collaborators. The Second Department found evidence that the Ukrainians were prepared to use bacteria (B. mallei) and cyanide. The poison was meant to be used against policemen and civil servants, while the bacteria was intended for military horses. The Polish historian Lucyna Kulińska mentions at least one incident in which five Polish army horses were successfully infected with B. mallei in Lwów (today Lviv) in October 1922.
Poland’s relationship with the Soviet Union remained tense in the mid-1920s and Soviet irregular forces frequently conducted cross-border raids into Poland. Renewed war with the Soviet Union seemed like a distinct possibility. Although a Soviet biological weapons program was not initiated until 1928, rumors about Soviet interest in biological warfare began to circulate earlier. In 1924 and 1925, the Polish press reported on early Soviet biological warfare research. For example, in January 1925, the Polish newspaper Rzeczpospolita reported how a “Soviet Professor Mastokovich” (presumably Petr Petrovich Maslakovets) had designed a new bacterial bomb, which promised to be decisive in the hands of the Bolsheviks.
What did Sosnkowski know about any of this? Sosnkowski was the deputy minister of military affairs in 1919 and would several times serve as minister of military affairs between 1920 and 1924. Afterwards, he would become a member of the powerful War Council, an advisory body on military matters. It is possible, even likely, that he was kept informed about these threats and that this influenced his actions in Geneva. It is a reasonable hypothesis, but it needs to be backed up by further research.
Sosnkowski was never naïve about what the League of Nations could accomplish. He had, after all, been instrumental in negotiating the military provisions of the Polish-French Alliance of 1921, which remained in force in September 1939. The French decision to respond to the German invasion of Poland with a declaration of war together with the United Kingdom was based on that original alliance. Sosnkowski therefore understood the need for military power and alliances. Nevertheless, he and others expected that the League would play a key role in upholding international security. If an agreement like the Geneva Protocol was violated, the League was supposed to step in and punish the perpetrator.
The Road to Chemical and Biological Warfare in World War II
The Polish attitude towards biological warfare was never strictly defensive. On the contrary, the Second Department started a small biological weapons program in the 1920s, which became significantly larger in the last years of peace. Oddly enough, researching this topic is much more difficult than examining the actual use of chemical and biological weapons during the war. The records of the Second Department were either destroyed during the Nazi-Soviet invasion or captured by German military intelligence, only to be captured again by the Soviets in 1945. Some of the files are presumably still in Russia. Although there are some primary sources available (for example a memorandum mentioning research to use artillery shells to disseminate bacteria on a battlefield), some of the best documentation about the Polish biological weapons program in the interwar years comes from a show trial that the Stalinist regime in Poland planned to stage in the 1950s. Scientists and technicians involved in the program were to stand trial for their alleged crimes. The show trial was abruptly cancelled by order of the Soviet government in 1953 and the people involved in the old biological weapons program instead received light prison sentences. At least one of the leading scientists, Jan Golba, had a very successful career in communist Poland until his death in 1976.
The background to the Polish interest in biological weapons came from a report from the military attaché in France regarding military research and a questionnaire from the League of Nations in 1923 regarding the prospect of both chemical and biological warfare. The League’s interest in biological warfare, as well as intelligence regarding biological weapons research in foreign countries, motivated the Second Department to start their own research and development program under the auspices of the Technical Division of the Second Department. According to a report from the head of the Third Division of the Second Department in April 1924, the Technical Division viewed the provision of both chemical and biological sabotage material as an urgent task. The material could be used for individual assassinations and for mass casualty attacks. In April 1924, Plan N was devised, which would include using sabotage with explosives and biological weapons as part of a defensive war against Germany. Primary targets were industrial plants and communication nodes in Germany. In May 1924, the Polish General Staff formulated Plan R for war with the Soviet Union and Germany at the same time. The plan envisioned using sabotage (in Polish, dywersja or diversions) deep inside enemy territory, including with chemical and biological weapons. Unlike other countries, the Polish armed forces appreciated the potential of unconventional warfare waged by special forces or — in case of an enemy occupation — by saboteurs in a stay-behind network.
Polish interest in biological warfare grew in the 1930s as it became clear that the League of Nations was unable to prevent the expansionist drive of Germany and the Soviet Union. The Polish biological weapons program grew, as noted by Polish historian Jan Widacki, notably through the building of the special “experimental station” in the fortress of Brześć. In addition, the Second Department pursued external partners. During the interwar period, Poland and Japan had a close intelligence collaboration, where they exchanged information about their common enemy, the Soviet Union. In 1936, a conference was held in Warsaw, where Polish and Japanese officers and scientists swapped information about biological weapons research.
Perhaps the linkage to the infamous Japanese Unit 731 can explain the darkest allegation about the Polish biological weapons program: the use of communist prisoners, sentenced to death, in human experiments with biological weapons. Following their demise their bodies would be chemically dissolved in an acid-resistant bathtub. The accusation of human experiments was supposed to play a key role in the planned show trial in the 1950s. The Japanese connection also explains the puzzle that one of the sources about the Polish biological weapons program in 1930s was U.S. military intelligence. In June 1945, U.S. military intelligence was very keen to learn more about Unit 731 and they interrogated the Polish Maj. Ludwik Kerstyn Krzewinski. He had been part of the Polish biological weapons program and knew about the collaboration with Japan in the interwar period.
Sosnkowski’s Involvement
Sosnkowski did not play a role in the Polish biological weapons program in the 1930s. In 1926, his friend and mentor Piłsudski launched a military coup against the democratic government, which turned Poland into a dictatorship. Sosnkowski was not a part of the plot and he reacted to the news by attempting suicide. After he had recovered, he resumed his military service and in 1936, he was instrumental in strengthening Polish-French military ties and securing a French loan for Polish rearmament, although his suggestions about preventive actions against a growing threat from Nazi Germany were ignored by the French government. The general’s influence in the Polish government diminished after the death of Piłsudski in 1935 and his proposal for a revised defensive plan in the summer of 1939 was ignored by the Polish commander-in-chief, Marshal Edward Śmigły-Rydz.
After briefly leading Polish forces during the German-Soviet invasion of Poland in September 1939, Sosnkowski fled the country and joined the newly created government-in-exile, where he would serve as the commanding officer for the Union of Armed Struggle until July 1941. The de facto leader of the Union of Armed Struggle and later the Home Army was Col. (later Gen.) Stefan Rowecki, who stayed in Poland during the occupation. Due to the long and difficult lines of communication through radio and couriers, most decisions would be taken by Rowecki and (following his arrest in 1943 and subsequent execution by the Germans) his successors in occupied Poland. Nevertheless, Sosnkowski was also a part of the decision-making process regarding the underground struggle in Poland.
Rowecki would regularly report from Poland about his intention to use biological and chemical weapons and what progress his subordinates had made in that regard. For example, in a March 1941 report to Sosnkowski, Rowecki wrote about the use of chemical and biological weapons so far. Attacks had resulted in 1,784 registered disease cases and 149 deaths among the occupiers. In addition, 680 horses had been infected with the bacterial agent B. mallei in 9 different locations. In May 1941, Sosnkowski informed Brig. Gen. Colin Gubbins, the deputy director of the Special Operations Executive, about a new laboratory for agricultural and forest sabotage where bacteria was produced and insects were bred for use in the German countryside. On at least one occasion, Sosnkowski would issue an order to Rowecki to increase the use of biological weapons due to a growing risk of a German invasion of the United Kingdom.
The Union of Armed Struggle and later the Home Army were not alone in using chemical and biological weapons in Europe. In fact, the they were not even the first to do so. The Czech resistance organization Obrana národa conducted experimental attacks with biological weapons before it was discovered and destroyed by the Germans in 1939–1940. Soviet partisans used poison and biological warfare against the Nazi occupation of Soviet territory. Soviet agents tried to assassinate Nazi officials like Wilhelm Kube and Curt von Gottberg or the Soviet renegade general Andrey Vlasov with poison. The role of the Special Operations Executive remains murky, but there is sufficient evidence to indicate that at least chemical weapons were transferred to Poland. On March 24, 1943, Maj. Harold Perkins of the Polish Section of the Special Operations Executive requested a report regarding the use of British-made poison (codenamed SACCHARINE) and was informed that, as of February 1943, the poison had been used against the enemy 189 times. In 1945 — following the Soviet conquest of Poland — the Special Operations Executive had to review its correspondence with the Polish government-in-exile regarding these activities. Chemical agents not delivered to the Home Army (1,158 ounces) had to be destroyed.
The Killing Fields of Poland
None of this changes the fact that the Union of Armed Struggle and the Home Army violated the Geneva Protocol. For the government-in-exile, they were a part of the Polish armed forces and no different than Polish soldiers fighting under allied command. They clearly acted with approval from the government-in-exile. The protocol has often been described as a “no-first-use” agreement, since it did not ban the research, development, production, and stockpiling of such weapons. Several countries reserved the right to use chemical and biological weapons in retaliation, which remained entirely legal until the signing of the 1972 Biological and Toxin Weapons Convention and the 1993 Chemical Weapons Convention. Even in this light, the Polish use of chemical and biological weapons was a violation of international law since Poland had not been attacked with such weapons.
It also does not change the fact that Sosnkowski played a role in the events, even though he was out of the loop for some time. In June 1941, Nazi Germany launched a surprise attack on the Soviet Union, thereby destroying the Molotov-Ribbentrop Pact and at the same time opening a door for rapprochement between the Soviets and the Western powers. Sosnkowski left the government-in-exile in July 1941 following the signing of a Polish-Soviet treaty, because the agreement did not specify the future borders of Poland in the east. In July 1943, following the death of Prime Minister Sikorski in a plane crash, Sosnkowski returned and was appointed as commander-in-chief of the Polish armed forces. In this capacity, he reported several times to the new Polish prime minister about the armed struggle in Poland, including the continued use of chemical and biological weapons. The last one seems to be the report from July 1944, which was mentioned above. On Aug. 1, 1944, the Home Army launched the Warsaw Uprising in an attempt to liberate the Polish capital before the arrival of the Soviet Army. The time of underground struggle was over. Instead of helping the uprising, the Soviets halted their advance outside Warsaw, offered only token support and allowed the Germans to finish off the Home Army. Poland was then ripe for a communist takeover.
What lessons can be drawn from this chapter of Polish history? Perhaps one should begin with what lesson should not be drawn. I have researched this topic for 10 years and once — after a lecture about this issue — a person thanked me for my presentation and then explained that he would have preferred the Poles had chosen to be exterminated rather than use such dreadful weapons. Although somewhat extreme, from a certain point of view this makes sense. Biological and chemical weapons are, according to the Geneva Protocol, “justly condemned by the general opinion of the civilized world.” There should therefore not be any room to use such heinous weapons, no matter the circumstances.
Obviously, such a view quickly falls apart when colliding with reality. History is full of societies that have been violently erased from their existence and Poland at times seemed destined to share this fate. For example, during the Soviet-Polish War in 1919–1921, the German Reichswehr and the Red Army secretly concluded an agreement stipulating that a Bolshevik conquest of Warsaw would trigger German paramilitary troops to occupy western Poland. In the meantime, the Reichswehr would sell the Bolsheviks surplus weaponry to be used against the Poles. Twenty years later this scenario became reality when Nazi Germany and the Soviet Union under the Molotov-Ribbentrop Pact attacked Poland and divided the country. During World War II, Poland lost six million of its inhabitants (22 percent of the population) and entire villages or towns — including Warsaw — were razed to the ground. Furthermore, Poland became a killing field under the Nazi policy of exterminating European Jews in places like Treblinka, Sobibor, or Auschwitz. In 1944–1945, Poland became a communist dictatorship and survivors of the Home Army were hunted down by the communist authorities as late as 1963. To add insult to injury, Poland lost one-third of its territory in the east, which became a part of the Soviet Union. The Western powers — the United Kingdom and the United States — accepted this outcome to maintain the alliance with the Soviet Union.
In short, there were certainly mitigating circumstances regarding the Polish use of chemical and biological weapons. It should also be noted that while the Home Army had more than 380,000 members in 1944, it always lacked ammunition and weapons. A Polish partisan fighting in Warsaw with a pistol or a few hand grenades against tanks and artillery would be regarded as well-armed by the Home Army. As someone whose family in Poland lost 20 relatives during the war (one was shot by the Soviets in Katyń, two others were killed by the Nazis in Auschwitz, a fourth, my great-uncle, “disappeared” when the Soviet Army arrived in 1944 — for years my grandmother and my mother would secretly listen to Radio Free Europe/Radio Liberty in the hope of hearing news about his fate), I make no pretenses that there were clear moral answers to the situation faced by the Poles.
There is also an element of tragedy in this tale. Sosnkowski was less motivated by idealism and rather by a strong dose of realpolitik when he negotiated the Geneva Protocol. Yet, it does not change the fact that the Polish government hoped to use the protocol and the League of Nations more generally to ensure Poland’s security. This policy ended in failure, since the league was never able to play the role it was meant for. Instead, the Poles during World War II were forced to rely on their allies and on their own military strength, including their secret biological and chemical weapons program. It was not enough. The Home Army, even with the use of chemical and biological weapons as a force multiplier, could never be strong enough to defeat the Germans and Poland’s Western allies turned their back on the Poles in 1944–1945. This is what in chess would be called “zugzwang” — every move one makes will end in defeat. In fact, when Sosnkowski openly criticized the passivity of the Allies during the Warsaw Uprising, the British government put pressure on the Polish government-in-exile and forced him to resign in September 1944. In 1945, the Western allies withdrew their recognition of the government-in-exile in favor of the Soviet-controlled government in Poland. For several years, Sosnkowski was neither allowed to return to the United Kingdom nor to visit the United States. As experienced by so many other Polish soldiers and officers fighting for the Allies, he was denied a military pension after World War II. Sosnkowski moved to Canada, where he died in 1969.
American historian John Toland once remarked that history does not repeat itself, but human nature does. As the post-World War II international order continues to crumble in the 21st century and the number of interstate wars increases, several countries will once again have to navigate rough waters between finding security in international law, in alliances with stronger partners, in their own military power, or in a combination of all three. The Polish case shows that none of these approaches will necessarily succeed. It is also a stark warning about what happens if a people with nothing left to lose has to fight with everything it has at its disposal. In the end it will come down to the will to survive, as expressed in the words (translated to English) of the Polish national anthem from 1797:
Poland has not yet perished,
So long as we still live.
What the foreign force has taken from us,
We shall with sabre retrieve.
Robert Petersen, Ph.D., is a special advisor at the Centre for Biosecurity and Biopreparedness in Denmark.
Image: Centralne Archiwum Wojskowe via Wikimedia Commons
