The document discusses chemical weapons use during World War 1, beginning with the Hague Conventions prohibiting their use. Germany was the first to deploy them, using tear gas mixed with explosives. They later developed more lethal gases like chlorine and phosgene. Mustard gas, introduced in 1917, caused severe blistering and infection. Chemical weapons inflicted cruel suffering compared to traditional means. Gas masks provided some protection but not from mustard gas. While Germany pioneered their use, the Ottoman Empire also engaged in chemical warfare by facilitating the Armenian Genocide through death marches and kill squads that murdered over 1.5 million Armenians between 1915-1922.