Any region, any period. I think that it would be very difficult to prevent ingrowth and other problems without precise clippers or scissors. How did people do it?
Not to dissuade other commenters, but you might be interested in these previous posts on the topic:
Thanks for the great question. There is always more to be discussed but in the meantime, some of the experts have already answered this question in the FAQ. Should give you a good start.
TLDR: Nail scrapers, knives, sharp rocks, biting. Tools for this date back to prehistory. The obsession with it throughout history indicates it was indeed a problem that was much worried about.