When was the poison gas invented?

Answer 1

I don't know when it was invented... probably in the first few years of WW1. I do know that it was first used in the battle of Ypres, 22 April - 25 May 1915. Although crude chemical warfare has been employed in many parts of the world for thousands of years (such as poisoned arrows or burning mustard gas balls.), "modern" chemical warfare began during World War I (see main article - Poison gas in World War I).[2] Initially, only well-known commercially available chemicals and their variants were used. These included chlorine and phosgene gas. The methods of dispersing these agents during battle were relatively unrefined and inefficient. Germany, the first side to employ chemical warfare on the battlefield,[3] simply opened canisters of chlorine upwind of the opposing side and let the prevailing winds do the dissemination. Soon after, the French modified artillery munitions to contain phosgene - a much more effective method that became the principal means of delivery.[4