Welcome to the Deep Dive. Today, we are looking
at a slice of history that honestly completely
rewrites how you might view modern warfare. We
really are. We're pulling from a huge comprehensive
set of notes today, all anchored by a really
detailed Wikipedia entry covering chemical weapons
in World War I. Right. And our mission for this
deep dive is to figure out exactly how the first
global total war of the 20th century earned this
incredibly grim title, you know, the chemists
war. Yeah, it's a heavy topic. But before we
get into the trenches, we want you to consider
a common assumption. Exactly. When you think
of the horrors of World War I, poison gas probably
stands out in your mind as like the ultimate
killer on the battlefield. Right. The defining
weapon. But the numbers in our sources tell a
very different story. Chemical weapons only accounted
for about three to three and a half percent of
the overall casualties. Which is wild. It really
is. It's a surprisingly low statistical footprint
for something so infamous. It is. But we have
to look far beyond those raw numbers to understand
the true impact here. The introduction of chemical
warfare fundamentally altered the psychological
landscape of battle. Oh, absolutely. It sparked
this frantic, terrifying scientific arms race
between the world's major powers. And it left
an environmental legacy that even now in 2026,
we are literally still unearthing. Yeah. To understand
the modern world relationship with weapons of
mass destruction, we just have to examine the
specific mechanics and the escalations of this
conflict. And to set the stage in partially here,
we really need to look at the legal and historical
reality of the era. Prior to the outbreak of
the war, you had the 1899 and 1907 Hague Conventions.
And they strictly prohibited the use of poison
or poisoned weapons in warfare. Yet the source
text shows us that once the seal was broken,
literally every major belligerent, Austria, Hungary,
France, Germany, the UK, the US, they all ultimately
developed and deployed these weapons. The sheer
scale of the conflict just created an environment
where military necessity entirely eclipsed those
international treaties. Yeah, it all just went
out the window. Exactly. But the escalation didn't
begin with, you know, a massive lethal cloud
of toxic gas. It actually started with weapons
engineered to be an annoyance rather than a killer.
Right, right. And that allowed military commanders
to test the waters of chemical warfare without
feeling like they were crossing a major red line.
Okay, let's unpack this because the very first
use of chemical weapons in the war was completely
non -lethal. Utterly non -lethal. In August 1914,
the French Army deployed 26 millimeter grenades
filled with ethyl bromoacetate, which is essentially
just tear gas. Right. And the quantities were
incredibly small. We are talking about 1 .2 cubic
inches of the chemical per cartridge. They deployed
it and the Germans literally did not even notice
they were being gassed. Which is almost comical.
The chemical just dissipated into the open air
and had zero tactical effect. Yeah, and the German
military actually had its own early failure a
few months later. Oh right, the winter attack.
Exactly. January 1915, during the Battle of Ballemoff
on the Eastern Front, they made their first large
-scale attempt. They fired 18 ,000 artillery
shells filled with liquid xylal bromide. Which
is another tear gas, right? Yep. Another lacrimatory
agent. They fired it at Russian positions, but
they fundamentally misunderstood the physical
chemistry required for the weapon to work. Right.
The weather. Yeah. Xylbromide needs to vaporize
to form an irritating cloud. But in the freezing
winter weather of the Russian front, the ambient
temperature was well below the chemical's vaporization
point. So just the liquid literally just froze
solid upon impact. Wow. It's fascinating how
the combatants justified this to themselves,
too, because none of the nations involved considered
the use of tear gas to be a violation of the
1899 Hague Treaty. No, not at all. The treaty
specifically banned projectiles containing asphyxiating
gas. There's the key word, asphyxiating. Right,
so the military lawyers and commanders argued
that tear gas was merely an irritant. It wasn't
designed to asphyxiate or kill you. It was just
designed to make you temporarily blind and force
you out of cover. In their minds, they were playing
entirely by the rules. And if we connect this
to the bigger picture, you can see how that kind
of legal technicality acts as a crucial stepping
stone. Oh, 100 percent. Once a military structure
justifies the logistics, the manufacturing, the
deployment of irritants, the leap to lethal chemicals
becomes a matter of degrees rather than a hard
moral barrier. And that barrier was completely
shattered on April 20, 1915. Second Battle of
Ypres. Exactly. The Germans deployed 167 tons
of liquid chlorine across 5 ,730 cylinders buried
in the trenches near Ypres in Belgium. Just waiting.
Yeah, they waited for a specific meteorological
window, a slight easterly breeze, and then they
just opened the valves. Chlorine is a true gas
at standard temperature and pressure, so it boiled
out of the cylinders and formed this massive,
creeping gray -green cloud. It drifted across
no man's land directly into the positions held
by French and Algerian troops. And these men
had no warning and no concept of what was rolling
toward them. It created absolute panic, resulting
in an 8 ,000 -yard gap in the allied line. And
the science of what chlorine does to the human
body really explains that panic. Yeah, explain
that part. Well, chlorine is a powerful irritant
that reacts aggressively with water. When inhaled,
it meets the moisture in the respiratory tract
and the lungs, and it immediately forms hypochlorous
acid and hydrochloric acid. It essentially destroys
the lung tissue from the inside out. So naturally,
the Allies immediately decried the attack as
a flagrant war crime. Of course. But the Germans
leaned right back on that same legal hair splitting
regarding the Hague Treaty. The treaty explicitly
banned chemical shells, meaning projectiles fired
from artillery. The Germans pointed out that
they had used cylinders fixed securely in the
ground to release the gas. They argued that because
they hadn't fired projectile, they hadn't broken
the treaty. It's quite the technicality. And
the British government was outraged, obviously.
But the military realities on the ground quickly
shifted their stance toward retaliation. Yeah,
they had to adapt. Lieutenant General Sir Charles
Ferguson of the British Army articulated this
shift pretty clearly. He stated that while it
was a cowardly form of warfare, the British could
not win. unless they killed or incapacitated
more of the enemy. So if that meant copying the
enemy's weapons, they must not refuse to do so.
Exactly. And that decision led straight into
the disastrous British debut of chemical weapons
at the Battle of Loos in September 1915. They
brought 140 tons of chlorine to the front, stored
in over 5 ,000 cylinders. Huge undertaking. But
this highlights the massive tactical flaw of
cylinder -based deployment. You are entirely
at the mercy of the wind. Right. When they opened
the valves, the wind proved incredibly fickle.
It lingered in no man's land and in several sectors
shifted completely, blowing the chlorine directly
back into the British trenches. And compounding
that meteorological failure was a severe logistical
breakdown. The troops found they couldn't even
release all the gas, because the quartermasters
had sent the wrong turning keys for the cylinder
valves. No, it was a disaster. You had British
soldiers choking on their own chlorine, struggling
with incompatible wrenches, all while German
artillery began shelling the British lines, rupturing
the unused canisters, and compounding the localized
gas concentration. That is just awful. So chlorine
terrified the troops, but for the military chemists
driving the arms race, it was flawed. It was.
It was highly visible, it smelled strongly of
bleach, and as we'll see in a moment, it was
relatively easy to chemically neutralize. So
the laboratories went to work to create something
invisible. Enter phosgene. Yes. Phosgene was
prepared by a group of French chemists led by
Victor Grignard. It was colorless, vastly more
lethal than chlorine, and it smelled faintly
like which made it incredibly difficult to detect
until a lethal dose had already been inhaled.
What's fascinating here is the insidious nature
of phosgene's chemical action. It possessed a
delayed effect of 24 hours or more. That's the
part that is just so grim. It really is. A soldier
could be exposed during a bombardment, feel relatively
fine, and continue fighting for an entire day
in the trenches. Thinking they were okay. Right.
Then, the next day, the cellular damage in their
lungs would reach a critical threshold, fluid
would rapidly build up, and they would suddenly
succumb. The source material shares a devastating
observation from historian Dennis Winter regarding
this. He noted that a fatal dose of phosgene
led to drowning spasms where a victim could discharge
four pints of yellow liquid from their lungs
every hour. Just horrific. It really is. That
specific detail strips away the clinical language
of casualties and shows you exactly what the
scientific advancement meant for the human beings
on the ground. And the arms rays did not peak
with phosgene. By 1917, a new agent arrived on
the battlefield that required a completely different
classification of warfare. Here's where it gets
really interesting because we are talking about
mustard gas. Oh, yeah. It became the undisputed
king of chemical terror in this conflict. The
most surprising detail in our sources is that
mustard gas wasn't actually a gas at all. No,
it wasn't. It was a heavy. volatile, oily liquid
that was delivered via explosive shells as a
fine aerosolized mist. And unlike chlorine or
phosgene, which only damaged the lungs when inhaled,
mustard gas was a vesicant, a blistering agent.
It attacked any exposed skin. Yes. It caused
immense painful blistering, severe temporary
blindness and internal bleeding. Because it was
an oily liquid rather than a true gas, it didn't
dissipate into the atmosphere. It settled. It
just coated everything. Everything. The soil,
the wooden trench boards, the mud, the equipment.
Depending on the weather, it remained active
and toxic for days, weeks, or even months. Troops
quickly realize the deadly fluid dynamics of
these heavy agents. Gas sinks. It flows like
water into the lowest points of the battlefield.
Right, into the trenches. Exactly. So soldiers
learn to abandon the relative safety of the trench
floor and stand up on the fire steps, those elevated
platforms used for shooting over the parapet.
Just to keep their heads above the invisible,
toxic tide pooling at their boots. That raises
an important question regarding mustard gas,
though. Why did military commanders favor it
if it only had a 2 % fatality rate? Well, as
our sources note, it was not a highly effective
killing agent compared to phosgene, but tactically
it was the ultimate harasser. How so? A dead
soldier requires a burial squad. A blinded blistering
soldier requires stretcher bearers, medics, hospital
beds, and sustained resources. It overwhelmed
the medical infrastructure and destroyed morale.
That makes a dark kind of sense. Nurse Vera Britton
captured the resulting psychological dread perfectly.
Oh, her quote is so powerful. She wrote, and
I'm quoting here, I wish those people who talk
about going on with this war, whatever it costs,
could see the soldiers suffering from mustard
gas poisoning. Great mustard -colored blisters,
blind eyes, all sticky and stuck together, always
fighting for breath, with voices a mere whisper
saying that their throats are closing and they
know they will choke. The sheer terror of these
evolving weapons necessitated an equally frantic
evolution in defensive engineering. Absolutely.
The very first countermeasures were improvised
out of pure desperation. When chlorine was first
deployed at Ypres, a Canadian medical officer
identified the chemical smell. He instructed
the troops to urinate on their handkerchiefs
or torn pieces of cloth and hold them tightly
over their faces. Just peeing on a cloth. Yeah.
The urea and ammonia in the urine chemically
reacted with the chlorine gas, neutralizing it
just enough to allow some men to survive the
cloud. And the attempts to industrialize a defense
were really fraught with fatal trial and error.
Back in Britain, the Daily Mail newspaper launched
a massive public campaign encouraging women to
sew cotton pad respirators for the troops. Over
a million manufactured in a single day. But the
design was fundamentally flawed. Deeply flawed.
When the cotton pads were dried, the gas passed
right through them. When the soldiers soaked
them in chemical neutralizers, the cotton fiber
swelled, completely blocking airflow and causing
the men to suffocate. Scores of soldiers died
directly because of these flawed pads before
the military urgently ordered them to be recalled.
Just a tragic mistake. But the engineering did
slowly improve. Major Clooney McPherson invented
the smoke helmet, which was essentially a flannel
bag soaked in neutralizing chemicals like sodium
thiosulfate. Right. It featured a small celluloid
window for visibility, and the soldier pulled
the entire bag over his head and tucked it into
his tunic. It was claustrophobic and hot, but
it worked far better than the cotton pads. The
culmination of all this defensive research was
the small box respirator, or the SBR. This is
that iconic disturbing visage you picture when
you think of World War I. Yeah, that classic
gas mask look. It featured a tight -fitting rubberized
face mask connected by a flexible hose to a distinct
box filter worn around the neck. The infantrymen
prized these respirators above almost all other
equipment. During a chaotic retreat, a soldier
might abandon his rifle or his pack, but he never
dropped his SPR. Never. And the logistics of
the war relied heavily on animals, so the chemical
threat applied to them equally. Researchers and
manufacturers had to design specialized gas masks
for horses, mules, messenger dogs, and even carrier
pigeons. Wow. Yeah, the entire living ecosystem
of the Army had to be shielded to prevent the
supply lines from collapsing under a gas attack.
You can just imagine the sensory overload of
the trenches during a gas alarm. Oh. It had to
be deafening. The visual threat of a creeping
cloud was matched by an auditory nightmare. Troops
used empty, spent artillery shells as makeshift
alarm bells, clanging them frantically. The British
deployed compressed -air strombus horns, massive
sirens that were so deafening they could be heard
nine miles away. Nine miles. That's incredible.
Wilfred Owen's famous poem, Duce et Decorum Est,
captures this perfectly, describing the ecstasy
of fumbling to get the clumsy helmets fitted
in time as the green sea of gas approaches. And
as the defensive masks became highly effective,
the offensive delivery systems had to evolve
to bypass them. Right, the cylinders weren't
cutting it anymore. Exactly. The early reliance
on buried cylinders was abandoned. They gave
the enemy too much warning and relied entirely
on cooperative weather. The tactical shift moved
toward artillery shells. Firing gas via artillery
meant there was no visible cloud rolling across
no man's land to trigger the alarms. The gas
simply exploded directly on top of the target
regardless of wind direction. The British engineering
response to this was the Leibniz projector. Ah,
yes. Instead of a standard artillery gun, this
is a large simple mortar tube sunk at an angle
into the ground. It could fire a massive 40 pound
cylinder of chemical agent over a mile. A 40
pound cylinder? Over a mile away. By wiring dozens
or even hundreds of these projectors together
and detonating them electrically at the exact
same moment, they could instantly saturate an
entire enemy sector with tons of dense gas before
a single soldier had the time to reach for their
mask. So... What does this all mean when we look
back at the conflict? We see an incredible escalation
of deadly science and delivery methods, yet the
final statistical reality of our sources shows
1 .3 million total casualties from gas, but only
90 ,000 fatalities. And that wide disparity between
casualties and fatalities exists because the
countermeasures ultimately kept pace with the
chemistry. The masks worked. They really did.
The evolution of the gas masks saved countless
lives. In 1915, the British fatality rate for
gas casualties was around 3%. In 1916, when Fosgene
and new agents were heavily introduced, that
fatality rate spiked to 17%. But by 1918, gas
was being used constantly as a standard weapon
to support almost every conventional artillery
barrage. Despite that omnipresence, the widespread
deployment and rigorous training with the small
-box respirator brought the fatality rate back
down to below 3%. That statistical survival rate
was highly dependent on industrial capacity though,
which varied wildly between the belligerent nations.
Very true. The Russian forces fighting on the
Eastern Front suffered a vastly disproportionate
toll, taking over 56 ,000 fatalities. Their army
simply lacked the domestic manufacturing base
to produce and distribute effective countermeasures
to millions of troops. They face the same advanced
chemistry as the Western Allies, but with a fraction
of the defense of engineering. And the impact
extended well beyond the uniform combatants.
While the belligerents generally did not target
civilian populations with chemical weapons, the
stagnant front lines were often drawn directly
through towns and villages. Caught right in the
crossfire. Right. In the town of Armentier, a
heavy German bombardment utilizing mustard gas
resulted in 675 civilian casualties. The civilians
had basic shelters and rudimentary masks, but
they did not understand the specific fluid dynamics
of the Vesicam. The heavy oily mist of mustard
gas just settled into their basements and cellars
where they were hiding. Exactly. Lingering for
weeks and causing devastating injuries long after
the artillery stopped firing. And that lingering
danger dictates the geography of Europe to this
day. At the end of the war. Over 16 million acres
of land in France had to be completely cordoned
off. 16 million acres. Even now, over a century
later in 2026, farmers in parts of France and
Belgium are dealing with the iron harvest. That's
right. Every spring, the frost heave pushes unexploded,
highly toxic chemical shells up to the surface.
Farmers literally plow them up, carefully placing
them on the edges of their fields for specialized
government bomb disposal units like The French
security tastes of yield to collect. It's just
a regular part of farming for them. Any of the
disposal of these chemical stockpiles immediately
following the armistice was incredibly reckless
by any modern standard. Mind -bodlingly reckless.
The victorious nations possessed millions of
tons of leftover chemical agents and no safe
methodology for destroying them. Huge quantities
were destroyed thermally at sites like Verdun.
They simply piled the shells up and burned them.
Which resulted in severe heavy metal and arsenic
contamination of the topsoil that persists today,
preventing anything from growing there. Even
worse, hundreds of thousands of tons of unused
chemical munitions were loaded onto ships, taken
offshore, and dumped directly into the oceans.
Just unbelievable. The sheer scale of the environmental
negligence is staggering. But the public revulsion
to what happened on the battlefields did force
a change in international law. The Geneva Protocol.
Yes. In 1925, the international community signed
the Geneva Protocol. It officially banned the
use of asphyxiating poisonous or other gases,
and of all analogous liquids, materials or devices
in international armed conflicts. It was a landmark
agreement, obviously, driven almost entirely
by the public viewing these scientific advancements
as a barbarous, inhumane invention. But the legal
phrasing contained a massive intentional loophole.
There's always a loophole. Always. The 1925 protocol
explicitly banned the use of these weapons in
a war. It did not ban the stockpiling, the research,
or the production of them. It essentially stated
that a nation could not be the one to use them
first. Which leaves you with a chilling final
thought to ponder as we wrap up today's deep
dive. Because of that exact legal loophole, the
chemical arms race didn't stop. It just went
underground. Right. During World War II, the
major powers utilized advanced chemistry to build
up stockpiles of nerve gases and mustard gas
that completely dwarfed the amounts used in World
War I. Britain stockpiled over 40 ,000 tons.
Wow. The United States amassed over 87 ,000 tons.
The Soviets produced 77 ,400 tons. And the reason
those chemical weapons were not widely unleashed
on the battlefields of World War II in Europe
wasn't because the weapons were unavailable.
No. It was because the psychological horror of
World War I had created a terrifying unspoken
stalemate. Yeah. Every side knew exactly what
would happen to their own cities and troops if
they pushed that button and initiated chemical
retaliation. A fragile global peace maintained
exclusively by the memory of horror. Yet because
the nation spent decades building those massive
stockpiles, millions of tons of those unused
World War II weapons eventually joined the World
War I leftovers. Dumped indiscriminately into
our oceans by the ship full. Which means the
true final casualties of the Chemist's War might
still be waiting for us, silently rusting in
the waters of our future. A sobering thought.
Definitely. Thank you for joining us on this
deep dive. Keep questioning the history that
shaped our modern world and we'll catch you next
time.