Germany first used poison gas on a large scale in this Western Front battle of World War I.
1st Champagne
2nd Ypres
Loos
Verdun
2nd Ypres. On the evening of April 22, 1915, nearly 170 tons of chlorine gas was released along a four-mile front. This was not the first gas attack of the war but was the first of such magnitude. Within 10 minutes, approximately 6,000 French and colonial troops had died from the asphyxiating gas. Even the Germans were surprised by the effectiveness of the weapon and had no reserves ready to properly exploit the situation.