WWI Chemical Warfare: Poison Gas & Gas Masks

Instructor: Nate Sullivan

Nate Sullivan holds a M.A. in History and a M.Ed. He is an adjunct history professor, middle school history teacher, and freelance writer.

In this lesson we will learn about chemical warfare during World War I. We will explore how poison gas was used, how effective it was in battle, and what measures were used to combat it.

World War I: A War of 'Firsts'

Imagine being a soldier entrenched in the ground and seeing a yellowish fog roll in. At first you don't know what to make of it. Then you begin to smell an odor. It smells like garlic - no wait, more like mustard. Your eyes begin to water and your skin begins to itch and burn. You have to get away from it, but there's no where to go: if you attempt to leave the cover of the trench, you'll be gunned down by enemy soldiers across the battlefield, and yet if you stay, you die choking on this burning yellow cloud! It's everywhere.

This was the experience of some to poison gas in World War I. In many respects World War I, the war fought between several European powers (and eventually America) from 1914-1918, can be thought of as a 'war of firsts.' The aircraft, tank, machine gun, and other technologies first saw widespread use in World War I. And of course, another important invention that was new to the war was the use of poison gas, or what we would call chemical warfare. Chemical weapons scared the daylights out of ordinary soldiers; it's not surprising when you consider the scenario described earlier! It was a powerful new weapon that caused unspeakable agony to those exposed to it.

Soldiers in World War I commonly wore gas masks to protect themselves from poison gas.

A Brief History of Chemical Warfare

Now in some senses we could say chemical warfare dates back to ancient times. For example, various people groups around the world have tipped their arrows, spears, swords, and other weapons in various poison substances. In the Middle Ages, Leonardo da Vinci actually proposed using an arsenic-based powder in war. This would cause those who breathed it to asphyxiate. We could consider this chemical warfare. But in regard to modern chemical warfare, World War I was the first conflict in which it was applied on a large scale.

Chemical Warfare in World War I

Before World War I broke out, poison gas used for military purposes had been prohibited under the Hague Conventions of 1899 and 1907. Basically these were treaties agreed to by the international community. The international community basically said, 'Okay, this poison gas is really nasty, bad stuff. We need to all agree not to use in in the event of war.' Of course, once World War I broke out, this agreement went out the window.

Tear gas and other mild forms of chemical weapons had been used by both the French and Germans in the beginning of the war, but the first major use of lethal gas took place at the Second Battle of Ypres in April 1915 when German forces deployed chlorine gas against the French. Relatively few died from the gas attack, although injuries were more widespread. Recognizing the possibilities for chemical warfare, Germany began to mass produce the poison chlorine gas, which is a green, gaseous form of the stuff that makes your eyes sting when you go swimming.

Chlorine gas initially irritated the eyes and throat, but prolonged inhalation produced excessive coughing and eventually asphyxiation. A few months later the Germans introduced the Russians to chlorine gas, resulting in an estimated 1,000 deaths. Chlorine gas produced a greenish cloud that was easily identifiable.

Another commonly-used poison gas was phosgene gas, which was actually more effective than chlorine gas. Phosgene was colorless and had an odor that was relatively difficult to detect. However, phosgene did not kill or wound soldiers immediately; it took 24 hours or so for symptoms to present themselves. It has been estimated that phosgene gas resulted in 85% of the deaths from poison gas in World War I.

Soon other nations (including the United States) jumped on the chemical weapons bandwagon and started manufacturing poison gas. Probably the most well known poison gas deployed in World War I was mustard gas, named because it gave off an order resembling the smell of mustard. Mustard gas was heavier than air, formed as a yellowish cloud, and tended to settle in low areas (such as trenches). Mustard gas caused severe blisters and chemical burns on the skin and in the lungs. Prolonged exposure caused internal bleeding leading and ultimately death. Mustard gas was first deployed in July 1917 by the German Army.

A soldier agonizes after receiving mustard gas burns.

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