ON THIS DAY ·
Chlorine gas attack at Ypres
22 Apr 1915 — A green-yellow chlorine cloud rolls over French colonial troops at Langemarck: the first mass poison-gas attack. By 1918 gas has killed some 90,000 and maimed a million more. Remember what industrial chemistry did here.
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The moment in context
With the Western Front blocked, both coalitions looked elsewhere for a decision. Germany used poison gas at Ypres and opened the age of chemical warfare. Italy joined the Entente in exchange for promised Austro-Hungarian territory and began a long series of attacks along the Isonzo river. At Gallipoli, Allied forces tried to force the Dardanelles, resupply Russia and drive the Ottoman Empire out of the war, but the Ottoman defenders held the ridges and the operation ended in evacuation.
From Gallipoli and the widening of WWI, chapter 6 of The Great War, 1871–1923 (NOV 1915).
The place: Chlorine gas attack at Ypres — map and full story →
Teach this in 5 minutes
- Why it happened — The “easterner” temptation. If the Western Front is a wall, said London’s easterners, go around: the Dardanelles, Salonika, Mesopotamia. The logic was real — knock out weak…
- The turn — Gorlice–Tarnów, 2 May 1915. The war’s most consequential forgotten battle: a four-hour hurricane bombardment on a narrow front — the method later perfected everywhere — and the…
- What it changed — Russia wounded where it cannot heal. The army recovers — 1916 will prove it — but the home front does not: refugees choke the cities, inflation eats wages, and the Tsar at headquarters…
Then ask the room: Gallipoli: a brilliant strategy ruined by execution, or a bad idea rescued by nothing? The argued answer is on the chapter page →
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