Here's a timeline of key moments:
* Ancient Times: While not chemical weapons in the modern sense, ancient armies used substances like sulfur dioxide and smoke to create clouds that could disorient or suffocate enemies.
* 18th Century: Chlorine was first isolated and recognized as a potential weapon in the 1770s, though its potential was not fully understood.
* 19th Century: In the mid-1800s, military strategists started exploring the use of toxic chemicals.
* World War I: The widespread use of poison gas as a weapon began in 1915 during World War I. Germany, in particular, was a pioneer in its development and used chlorine gas, phosgene, and mustard gas against Allied forces.
Therefore, it's more accurate to say that poison gas wasn't invented at a specific moment, but rather gradually developed and refined over several centuries, culminating in its first large-scale use during World War I.
