Already subjected to constant bombardment by artillery, enemy sniper fire, and the awful living conditions, soldiers fighting in the muddy trenches of the First World War did not imagine their situation could get any worse. Then, from April 1915, a new nightmare began: gas warfare. Lethal poisonous gas was first used by the German Army in the war, but it was soon adopted by all sides. Although there were often terrible and lasting consequences for the individual soldiers who experienced a gas attack, the weapon did not prove strategically decisive since wind and countermeasures like gas masks frequently negated its effects.
This is a companion discussion topic for the original content at https://www.worldhistory.org/article/2839/the-terrors-of-poison-gas-in-wwi/.