In the middle age people smoked, smoked herbs, smoked pipes, and this gives some good situations in which use it.
For europe that's not documented i believe.
From 13th century cannabis smoking was introduced in subsahara africa mainly the horn of africa by eastern traders. (cannabis originates from the area of modern day india's north eastern states/assam.)
Tobacco was introduced about 2 centuries later by european traders (from the americas).
In fact, smoking tobacco only became popular around the 17th century in europe, the arabs got popularly 'hooked' on tobacco much quicker.
Smoking is as old as human civilization for the americas(tobacco and the billions of cool plants they get from the amazone) and eastern Asia(china and india, cannabis) but europe/meditereanan civilization only got introduced to it much later.
The romans where also well familiar with canabis and hemp threw trade with india(they used it for alot of things on a huge scale), but as far as i know they didn't smoke it, for recreational use they ate it in a preparation with dried fruits and ghee(purified butter) like most indians around that time. (even in india smoking canabis threw mostly chillums is only about 2 k years old)
Perhaps some heretics burned herbs earlier, but they didn't directly inhale it threw a pipe for example(which i define as smoking), that happened much later in europe.
A shame i am 25 min late with this post...
But you know what they say about timing and stoners...
