Apr 22, 2015 | 16:00 GMT

8 mins read

World War I and the Legacy of Chemical Weapons

Soldiers from the Australian 4th Division at Garter Point near Zonnebeke, Ypres sector, Sept. 27, 1917.

There are few weapons in war as nefarious as poison. One hundred years after the Germans first used chlorine gas during the Second Battle of Ypres, chemical weapons remain widely stigmatized and outlawed. Of all the technologies from World War I that went on to redefine combat in the 20th century, chemical weapons have the most sordid legacy.

Ultimately, however, the use of lethal and incapacitating gasses proved largely ineffective in conventional warfare. They were comparatively easy to counter, difficult to use and rarely achieved the desired or planned result. The impact of chemical weapons is less practical than it is psychological, which partly justifies the reluctance to use such measures but also explains why many countries still have chemical stockpiles.

At 5 p.m. on April 22, 1915, the Germans released around 168 tons of chlorine gas, using the prevailing wind to carry the toxic cloud toward the French 45th and 87th Divisions at Gravenstafel. The gas worked far better than anticipated, creating chaos among the French, Moroccan and Algerian troops and opening a 7-kilometer (4-mile) gap in the defensive line. The Germans failed to effectively capitalize on the break; surprised by the effectiveness of the gas, they were unprepared to exploit the situation. For military planners on all sides, however, the apparent usefulness of poison gas had been proved.

The main reason for the effectiveness of the first chlorine attack was that the troops on the receiving end did not know what they were facing. As the green-tinged cloud washed over them and the chemical began taking effect, panic struck, resulting in many soldiers either running away or dropping down into the trenches. Both options proved fatal for many. By withdrawing with the movement of the cloud, many prolonged their exposure to the gas. And for those who sought refuge in the trenches, the heavier-than-air gas sunk into the secluded spaces, creating a poisonous environment.

Yet for the remainder of the war, the Germans never saw a repeat of the rout at Gravenstafel, even with deadlier gasses and improved delivery methods. The chemical genie had been released from the bottle, and once the secret was out, all sides worked to perfect their own weapons while mitigating the risk of the enemy's. This is not to say that there were no casualties, but out of the approximately 16 million fatalities in World War I, chemical weapons caused less than 100,000. Instead, artillery was by far the greatest killer of the war, accounting for around 60 percent of all fatalities. But the use of poison gas is irrevocably burned into the collective memory of the nations that participated in the conflict. It is perhaps the psychological impact of chemical warfare that lingers more than its physical toll.

The Chemist's War

The principles of chemical (and biological) warfare have been around for thousands of years, but it was not until the industrial age that harmful agents were successfully manufactured, bottled and shipped in vast quantities. Going into the war, Germany had an expansive chemical industry. As a byproduct of the development of industrial compounds, dyes and agricultural products, German chemists unlocked the door to noxious vapors and liquids that could be easily weaponized.

The world's first industrial war was rapidly driven to stalemate on the Western Front between opposing forces unable to outmaneuver or break the defenses of the other. It was inevitable that creative and scientific minds would consider unorthodox ways to gain advantage. The Spartans used chemical weapons during the Peloponnesian War to displace sentries, burning sulfur to form a harmful gas. It was hoped the same effect could be achieved by modern means. In the era of the professional soldier, however, there were many traditionalists that considered chemical weapons to be dishonorable, even cowardly. There were even Hague conventions prohibiting their use. But as the stalemate dragged on and the death count continued to rise, the stubborn practicality of warfare eroded the desire for caution or restraint.

The French and Germans used fairly benign tear gas in the first year of the war, but the effects were almost unnoticeable. What had become a very symmetric war led almost inevitably to asymmetric thinking, fueled by an age of technical innovation. The quest was for a decisive weapon, one that could break the line and bestow a battle-winning advantage on the first side that used it. It was hoped that poison gas would be that panacea, but the success of April 22 was never to be repeated.

Despite the rigorous methods that went into developing and weaponizing chemicals for the battlefield, the deployment was far less scientific. Success was largely dependent on the prevailing wind, as the British learned with mounting horror at the Battle of Loos. When the taps were opened on the "white star" containers (denoting chlorine in the English nomenclature), a change in the wind blew the released gas back toward friendly troops, resulting in catastrophe.

German soldiers take advantage of a suitable wind to emit poison gas from cylinders, circa 1915.


The best use of chemical weapons was for area saturation and denial. The more prolonged the exposure, the more lethal the effect. The problem with gas — even the more deadly types, such as phosgene — was that it was not persistent. Gas masks were rapidly developed and delivered to soldiers on the front line with instructions on how best to survive a gas attack: mask up, stay on the parapet and wait for the cloud to pass.

Gas shells later obviated some of the random effects of wind, but while gas rounds could be delivered on target and at range, the required level of saturation was often lacking and equally at the mercy of a stiff breeze. The only exception was mustard gas, which landed in the desired concentration, survived as a persistent liquid and provided suitably appalling effects. But mustard gas, as horrible as it was, killed only a fraction of those exposed.

To Be Gassed

Chemists were very good at explaining the properties and compositions of the weapons they produced. Doctors, through treating those exposed to chemical weapons, became adept at describing the specific physiological effects on the body. Psychologists, nicely insulated from the front lines, were still wrapping their heads around the concept of "battle shock" but could recognize the fear response that poison gas instilled. But the most graphic accounts of what chemical weapons could do to the body and mind came from the soldiers themselves — and the nurses that treated them at the dressing stations. Chemical weapons instilled fear like almost nothing else.

Of all the ways to die in World War I, death by gas was among the most dreaded. As well as infecting the minds of young soldiers with fear, reports soon filtered back to the civilian population, affecting the public consciousness and further diminishing popular support for the war effort. The thought of young men taking weeks to die, blinded and in constant agony was almost too much to bear. Conditions in the trenches were already appalling, and ingenious modern weapons, such as phosgene and mustard gas, were only exacerbating the situation. To understand the acute effect chemical weapons had on the psyche of the World War I soldier, it is perhaps the war poets — Wilfred Owen, John McCrae, Robert Graves and Siegfried Sassoon, to name a few — and writers such as Erich Maria Remarque that explain it most profoundly. 

Though chemical weapons killed a comparatively small number of people in World War I, as many as a million soldiers and civilians were exposed, many of whom would carry debilitating symptoms for the rest of their lives. Following the armistice, the horrors of war returned with the surviving soldiers and gas was at the forefront. The psychological effect of poison gas far outweighed its usefulness as a casualty-causing weapon, and continues to do so.

A German officer leads his men through a cloud of phosgene gas as they run toward the British trenches, circa 1916.

(General Photographic Agency/HENRY GUTTMANN/Hulton Archive/Getty Images)

The Legacy

While the 1925 Geneva Protocol officially banned chemical weapons in war, countries continued development and stockpiling. The changing nature of battle meant that chemical weapons had little play in World War II combat, though large arsenals were amassed. The limitations of chemical weapons had been writ large in the Great War, and saturating wide swathes of land with noxious vapors for short periods did not necessarily fit into the concept of Blitzkrieg. Also, training, knowledge and protective equipment effectively mitigated the effects and utility of chemical weapons. However, German scientists still maintained an edge, developing the first nerve agents, including tabun, sarin and soman. These were never used, although consideration was given to installing chemical warheads in V-2 rockets. But the Germans realized that chemical weapons had a very specific utility, when employed in confined spaces for the purposes of mass murder.

Although huge amounts of chemical weapons were produced and stockpiled during the Cold War, they have been used only a handful of times in the latter half of the 20th and early 21st centuries, most notably during the Iran-Iraq War in the 1980s and most recently in Syria. On each occasion, the public outcry and international condemnation was fierce. Chemical weapons continue to be heavily stigmatized, fairly ineffective and largely indiscriminate. They also remain difficult and expensive to store, because of their corrosive nature and susceptibility to temperature and moisture, as well as to dispose of. The United States has already neutralized the bulk of its chemical weapons stockpile, at a cost of around $1 billion per 1,000 tons. Washington has also assisted with the disposal of post-Cold War chemical weapon arsenals, most recently addressing the estimated 1,000 tons possessed by Syria. It will take decades to destroy or neutralize the remaining stockpiles in existence. While ineffective, chemical weapons maintain their poisonous legacy, both in the mind and hopefully sealed in the last remaining storage facilities. 

Editor's Note: In acknowledgement of those who died during the first use of lethal poison gas in World War I, Stratfor is publishing this analysis at the exact time the chemical attack began, during the Second Battle of Ypres, April 22, 1915, at 5 p.m. local time.

Article Search

Copyright © Stratfor Enterprises, LLC. All rights reserved.

Stratfor Worldview


To empower members to confidently understand and navigate a continuously changing and complex global environment.