French soldiers near the Belgian village of Langemark, in what was to become known as the “Ypres Salient,” did not know what to make of the green, earth-hugging cloud that came rolling toward them from the German trench line. Earlier, the enemy artillery had ceased, and things had gone quiet for a while. Then it started up again just before the wind rose and the cloud appeared. This was not the ordinary smoke or dust of war. It was something new.
It was, in fact, chlorine gas. The Germans had launched, on April 22, 1915, the first lethal gas attack in the history of war. It was a stark violation of an international treaty negotiated and signed at The Hague in 1899 by all the combatants in this war. The Germans, nevertheless, insisted they had done nothing wrong. According to the strict language of the treaty, signatories were “to abstain from the use of projectiles the object of which is the diffusion of asphyxiating or deleterious gasses.”
Their gases had been released from cylinders, not projectiles, the Germans argued, so this didn’t count as a violation.
The legalistic distinctions were, almost certainly, a matter of indifference to the troops against whom the attack was directed. When they inhaled the green mist, it burned the lining off their lungs, and they choked on it—choked, in many cases, to death, after going blind and mad with pain and terror.
In just a few minutes, the gas had killed some 5,000 men and opened a four-mile breach in the French lines as men either died or left their trenches and fled for the rear, leaving the way open for a German attack. The opportunity was there, perhaps, to roll up the enemy’s flanks along the breach and then push on, even to the Channel.
In strict military terms, this first use of gas in a surprise attack was an impressive success. But, as so often in what became known as the Great War, the advantage was temporary and the opportunity wasted. The German command might have won the war if it had acted on the appeal of Fritz Haber, who later won a Nobel Prize for chemistry and was urging the leaders of his nation’s army to go all in on the gas attack in Ypres. But the German commander, Erich von Falkenhayn, did not have the troops on hand to exploit the opportunity that the chlorine gas had given him. This was typical of Falkenhayn, who later missed another opportunity against the French, at Verdun. In the words of the military historian B. H. Liddell Hart, “Like Napoleon’s opponents, [he saw] ‘too many things at once,’ and above all saw the enemy’s strength too clearly. . . . [He] ruined his country by a refusal to take calculated risks.”
But that was for later. In April 1915, the German Army attempted to duplicate that first attack a few days later, north of Langemark. German units opened canisters holding chlorine under pressure, and the wind carried the gas toward the enemy’s lines, followed by German infantrymen wearing crude respirators.
British and Canadian troops had not been issued equipment for protection, so they did what soldiers always do. They improvised: held scarves, handkerchiefs, and towels soaked in their own urine to their faces and breathed through the wet cloth. It worked, in many cases. Still, there were another 5,000 casualties, and ground was lost in the British section of the line, just as it had been in the French. Though there were several follow-up gas attacks in Ypres that spring, the Germans never achieved the total break-through that would lead to victory, and they had soon exhausted their stores of gas. Also, the winds changed and could not be counted on to blow in the right direction.
The gas attacks ceased. Temporarily.
Outrage had followed the news. One feels outrage, even today. The catalogue of horrors from the First World War is extensive. As Winston Churchill wrote, “All the horrors of all the ages were brought together, and not only armies but whole populations were thrust into the midst of them. . . . [And] when all was over, Torture and Cannibalism were the only expedients that the civilized, scientific, Christian States had been able to deny themselves: and they were of doubtful utility.”