An understatement if we dig far enough!
In Québec the legalized vilification of "Indian Hemp" was initiated while Canada still belonged to the British Empire as one of it's dominions. The official reference dates back to a law book printed in 1890, if i'm not mistaking, though i was under the impression that the legal article itself was actually corresponding to a 1885 revision. Here's the ancestor of all bigot anti-cannabic prohibitionist "schedules" anyway, consider it a prototype that paved the way for many more to follow:
L'Acte de pharmacie de Québec de 1885 - 53 Vict (1890) - Chapitre 46 (137328)
N.B.: "Indian Hemp" = "Chanvre Indien"
Take note that "Indian Hemp" was classified as "Poison" besides Arsenic and Cyanure.
Good day, have fun!!