This is a topic I'm interested in, the history of cannabis being used as drug though out history I feel that it has always been popular but there not much information about it I have always been interested in the topic if anyone has any other information about the uses of cannabis in History I'd be very interested. I hope that I may find answers and that others may find this interesting.
Minimal to none. Around 1910 it was not illegal, but also barely anyone knew of it especially in Europe. Recreational use would have been more common in Asia and South America. It was simply not very understood, known of or cultivated aside hemp for products such as rope and fabric. Cannabis became more popular towards the 1930s and 40s. From the 1940s you see the earliest "reefer madness" propaganda. Also the propaganda often had racist undertones as Marijuana was associated with Mexicans and they would get portrayed as dirty with the plant. But for uses in ww1 I't was quite unknown in the west. Perhaps some Ottomans smoked it to relax on the frontlines.
As a follow up to be more specific did soldiers use and if so who when and where?