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Which chemical agent did the German army release at the Second Battle of Ypres in 1915?
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chemical weapon
American soldiers participating in a simulated gas attack exercise, World War I.
At the Second Battle of Ypres in April 1915, the German army released nearly 200 tons of chlorine gas.3
This event marked the first large-scale use of poison gas as a weapon in World War I. The gas was deployed from thousands of cylinders along a 6-km front, creating a wind-borne cloud that caused significant casualties among French and Algerian troops and created a major breach in the Allied lines. While the attack was a tactical innovation, the German military was not prepared to fully exploit the resulting gap in the defense.12